Arsenal striker Pierre-Emerick Aubameyang has revealed his heart is "absolutely fine" and he is "completely healthy" after undergoing tests in London.

The Gabon captain returned from the Africa Cup of Nations on medical grounds without playing a game after cardiac lesions were discovered when he underwent health checks.

Aubameyang had tested positive for COVID-19 on January 6 following Gabon's arrival in Yaounde.

The 32-year-old on Thursday stated that he is back in training after getting the all-clear.

He posted on Instagram: "I came back to London to do some additional checks, and I'm very happy to say that my heart is absolutely fine and I'm completely healthy!!

"Really appreciate all the messages over the last few days and I'm already back at it."

Aubameyang has this week been linked with a loan move to Saudi club Al Nassr.

The former Borussia Dortmund man has not played for the Gunners since being stripped of the captaincy due to a breach of discipline last month.

Arteta said of his former skipper during a press conference on Wednesday: "He's in London and going through some examinations because we haven't had any clarity from Gabon about why he came back.

"So it's our obligation to make sure he's safe and in good condition. So far historically with what we've done with the player that's never been an issue."

Nigeria rounded off an impressive performance in the Africa Cup of Nations group stages with a 2-0 win over Guinea-Bissau.

Already assured of their place in the last 16, the Super Eagles moved into the knockouts as Group D winners with a 100 per cent record after making it three wins from three on Wednesday.

Umar Sadiq broke the deadlock with his first international goal in the 56th minute, given the simple task of tapping in a superb low cross from Kelechi Iheanacho, who moments earlier had forced Guinea-Bissau goalkeeper Maurice Gomis to turn over the crossbar with an audacious effort from more than 40 yards.

Captain William Troost-Ekong made sure of victory 15 minutes from time, prodding into an empty net on the rebound after the excellent Moses Simon had jinked past several defenders and rattled the bar with a fierce strike.

Troost-Ekong looked to have been denied by the offside flag, but a lengthy VAR review concluded with the award of a goal that put the game beyond doubt.

Guinea-Bissau rarely threatened a response, and head home having failed to score for a competition record seventh consecutive AFCON game.

Egypt secured their place in the Africa Cup of Nations knockouts by edging past Sudan 1-0 thanks to Mohamed Abdelmonem's goal. 

The seven-time AFCON champions took second place in Group D behind Nigeria, who defeated them in their opening game of the campaign, and look likely to face the Ivory Coast in the last 16. 

Sudan goalkeeper Mohamed Mustafa did well to deny Mostafa Mohamed but Abdelmonem got the better of him with a powerful header from the edge of the six-yard box following a corner in the 35th minute.

Mohamed Salah was unable to finish off a mazy run in the 60th minute and Amr El Soleya failed to make the most of a neat lay-off from the Liverpool attacker shortly after. 

Egypt's place in the knockouts was secured after Mohamed El-Shenawy saved Mohamed Abdel Raman's free-kick and got his head in the way of Mustafa Karshoum's follow-up, warding off the threat of a dramatic fightback from Sudan. 

Algeria could become the second major casualty of the Africa Cup of Nations as the group stages are concluded on Thursday.

The defending champions head into their final – and arguably toughest – Group E match in a desperate position after failing to impress in their first two outings.

Thursday will also bring an end to Group F, where Algeria's neighbours Tunisia have plenty of work to do as well.

Ivory Coast v Algeria (16:00 GMT)

With one point from two matches, Algeria head into matchday three bottom of Group E and staring into the abyss of elimination.

Only a victory against group leaders Ivory Coast will be enough to take them into the knockouts, otherwise they will fall at the first hurdle for the third time in five AFCON tournaments.

Ivory Coast will be hoping to gain a measure of revenge for their 2019 quarter-final penalty shoot-out defeat to the Fennec Foxes, with the Elephants heading into the game unbeaten in five AFCON games.

They too have something to play for, with top spot still up for grabs.

One to watch: Youcef Belaili (Algeria)

You certainly cannot fault the effort of winger Belaili, given his eight shots is three more than any of his team-mates and he has also tallied the most touches in the opposition's box (11), but there is little getting away from the fact Algeria in general need to sharpen up in front of goal if they are to avoid following Ghana into shock elimination.

Sierra Leone v Equatorial Guinea (16:00 GMT)

Before the tournament started, few would have given this pair much hope of finishing in the top two, yet either could grasp that opportunity on Thursday.

Equatorial Guinea are second and hold a one-point advantage, meaning a draw may well be enough to get them through at least as one of the best third-placed teams.

But Sierra Leone drew 2-2 with Ivory Coast last time out following a goalless stalemate with Algeria – the results showed they are not to be taken lightly.

Equatorial Guinea will be favourites, however, and they have only ever lost two of their eight AFCON group games.

One to watch: Mohamed Nbalie Kamara (Sierra Leone)

Kamara has been one of the standout goalkeepers at the tournament so far. His 12 saves are the most of anyone, and those stops have seen him record a 'goals prevented' record of 2.1, the second-best record among keepers at the AFCON.

Gambia v Tunisia (19:00 GMT)

Although Tunisia could potentially sneak through as one of the best third-place teams with their current haul of three points, it would be a disappointing group stage total for a side that came into the tournament with high expectations.

Yet the Carthage Eagles' situation is slightly complicated by the fact they recorded seven new positive COVID-19 cases in the build-up, with key players Wahbi Khazri and Ali Maaloul among them.

That will be a boost to Gambia, however, with the Scorpions aiming to become only the third AFCON debutants this century to go unbeaten in the group stage.

But Tunisia have not lost to an AFCON debutant since the 1996 final.

One to watch: Hannibal Mejbri (Tunisia)

Manchester United youngster Hannibal has been used sparingly in this tournament, playing just 45 minutes so far. Yet, his tally of two chances created is only bettered by Khazri and Maaloul (both on three), and given Tunisia's COVID-19 issues, a first start may be on the cards.

Mali v Mauritania (19:00 GMT)

A wonderful chance presents itself here for Mali, as they target topping Group F.

If they better Gambia's result against Tunisia, that is exactly what they will achieve, as well as extending their longest ever group stage unbeaten run to seven matches.

Anything other than a Mali win would be a significant surprise given Mauritania are bottom of the group and pointless, their five goals conceded second-worse to Ethiopia, who have played a game more.

One to watch: Ibrahima Kone (Mali)

Kone has played a prominent role in Mali's solid start to the tournament, scoring a penalty in each of their two matches. If he nets against Mauritania, he will be the first Malian to tally get three goals in a single AFCON edition since former Barcelona midfielder Seydou Keita in 2013.

Ghana were knocked out of the Africa Cup of Nations as they suffered a stunning 3-2 defeat to the Comoros.

Victory would have been enough for the Black Stars to progress as one of the best third-placed teams but a double from Ahmed Mogni gave the Comoros their first Africa Cup of Nations win in a Group C encounter that saw captain Andre Ayew sent off for the four-time champions.

The Comoros took a shock lead in the fourth minute as a quick break was finished off by El Fardou Ben Nabouhane with a confident strike into the bottom-right corner.

Ghana's problems deepened when Ayew was shown red as they pressed for an equaliser, the skipper deemed by VAR to have fouled goalkeeper Salim Ben Boina in an effort to prod home a rebound from Kamaldeen Sulemana's shot.

And the advantage of the extra man at the Comoros' disposal eventually told just after the hour as haphazard goalkeeping from Jojo Wollacott presented Mogni with the chance to double their advantage courtesy of an assured finish.

Richmond Boakye provided an instant response when he steered home a header from a right-wing corner and the turnaround looked to be on when Alexander Djiku tapped in a flick-on as the Comoros' defence failed to deal with the same set-piece with 13 minutes remaining.

A decisive fifth goal did arrive, but it was Mogni who had the final say as he was presented with a simple finish after excellent work down the right from Bendjaloud Youssouf to keep the minnows' hopes of qualification for the knockouts alive and condemn Ghana to a humiliating exit.

Achraf Hakimi's late stunner spared Morocco's blushes as it secured a 2-2 draw that takes them through to the next stage of the Africa Cup of Nations as Group C winners.

Coach Vahid Halilhodzic took the opportunity to rest several key men, but that decision backfired in the first half, with Gabon well worth their 21st-minute lead.

Jim Allevinah converted past Munir Mohamedi after Nayef Aguerd slipped at the crucial moment, and they might have made it to the break with a bigger lead were it not for the Morocco goalkeeper.

The Atlas Lions thought they had equalised with an hour played when a long ball from the back was missed by Gabon goalkeeper Jean Noel Amonome and went all the way in, but Youssef En-Nesyri was deemed to have been interfering with play in an offside position.

Morocco did get a slice of fortune 16 minutes from time, substitute Sofiane Boufal winning a penalty despite Andre Biyogo Poko appearing to win the ball, and the Angers attacker converted from 12 yards.

Gabon – without Mario Lemina and Pierre-Emerick Aubameyang again – thought they had snatched a win to top the group as Aguerd put into his own net after 81 minutes, but Hakimi's free-kick three minutes later rescued Morocco.

Wednesday's action at the Africa Cup of Nations sees Group D conclude with two heavyweights seemingly set for the knockout phase.

Egypt certainly have not been without their critics in this tournament, with the performances turned in by Carlos Queiroz's men far from spectacular, but they remain on the brink of progression.

Assuming they get the job done, they will join Nigeria in the next round after the Super Eagles won both of their first two matches.

The two giants of AFCON football will be expected to prevail on Wednesday.

Guinea-Bissau v Nigeria (19:00 GMT)

Considering Nigeria have come into this tournament essentially under the guidance of a caretaker manager in Augustine Eguavoen, the Nigerian Football Federation's technical director, they have made a very solid start.

They head into matchday three with six points from two games and have the chance to win all three first-round matches for the first time since 2006.

Nigeria will be massive favourites as well. Guinea-Bissau have never won an AFCON game in eight attempts, with only Benin (14), Mozambique (12) and Namibia (nine) playing more tournament matches without a single success.

Their issue this time around has been an obvious wastefulness in front of goal, failing to score from 16 shots that convert to an expected goals (xG) total of 2.2 – if they are goalless in this game, Guinea-Bissau will become the first team in AFCON history to go seven successive matches without scoring.

One to watch: Taiwo Awoniyi (Nigeria)

Union Berlin forward Awoniyi may be a relatively new face at international level, but he has looked a prominent threat for Nigeria. His nine shots over the first two games was more than twice as many as any other Super Eagles player, while his 14 touches in the opposition's box is also the most of anyone in the squad. Still, one goal from 2.4 xG suggests he could sharpen up a little.

Egypt v Sudan (19:00 GMT)

A point will be enough for the Pharaohs to follow Nigeria into the knockouts, though their defeat to Eguavoen's men means second place is the best they can hope for.

Egypt have looked every inch a side reliant on Mohamed Salah in this tournament, with his goal against Guinea-Bissau last time out breathing some life into their campaign.

While a draw will be enough for them, in reality only a win over Sudan will satisfy the expectations of supporters.

Sudan's xG total (1.25) and xGA (expected goals against) of 3.17 are the worst of the four teams in Group D, and Egypt will hope to capitalise on their lack of defensive solidity and attacking threat.

One to watch: Ali Achrine (Sudan)

If Sudan are to stand any chance of beating Egypt and potentially going through to the knockout phase, goalkeeper Achrine will surely need to be in inspired form.

Guinea faced an anxious wait but will still qualify for the Africa Cup of Nations round of 16 despite suffering a shock 2-1 defeat to Zimbabwe at Stade Ahmadou Ahidjo.

Kaba Diawara's side started their final Group B match with one foot seemingly in the knockout stage, but Zimbabwe pulled off an upset to end their 14-match winless run in Yaounde on Tuesday.

Guinea then had to wait for confirmation that Sengal and Malawi had drawn 0-0 in the other game before being sure of their place in the next stage.

As a result, Senegal finished top of the group, meaning they will play one of the best third-placed teams, while Malawi finish third behind Guinea by virtue of an earlier defeat to them.

Captain Knowledge Musona rose unmarked to open the scoring for Zimbabwe - with no chance of qualifying after losing their two other games - after 26 minutes, heading home Never Tigere's cross from six yards out.

Kudakwashe Mahachi doubled Zimbabwe's lead two minutes before half-time, with goalkeeper Aly Keita badly at fault as he failed to keep out the midfielder's shot from outside the penalty area.

Guinea looked a totally different side after the break and Naby Keita halved the deficit four minutes into the second half, bursting forward and unleashing a rasping left-foot strike from outside the box that flew into the far corner of the net.

Zimbabwe came under increasing pressure but held on for their first AFCON win since 2006, while Syli Nationale will need to improve markedly to make an impact in the knockout stages.

Senegal secured their spot in the knockout phase of the Africa Cup of Nations as Group B winners after a late penalty reprieve saw them draw 0-0 with Malawi.

The Teranga Lions came into the tournament as one of the favourites, and while they progress to the next stage at the top of their group with five points, it was by no means convincing.

Malawi looked to carry the greater threat in the first half, with Gabadinho Mhango seeing a couple of long-range efforts go close.

Senegal did at least test Charles Thom in the Malawi goal early in the second half, with Abdou Diallo's header tipped just over, though it was hardly a sign of imminent domination.  

Malawi then looked set to take the lead with 15 minutes left when Bouna Sarr conceded a penalty for appearing to foul Gomezgani Chirwa, but the decision was overturned after a VAR check, much to the Flames' fury.

As a result, Senegal finished top of the group, meaning they will play one of the best third-placed teams, while Malawi finish third behind Guinea by virtue of an earlier defeat to them.

Guinea face an anxious wait to discover if they will qualify for the Africa Cup of Nations round of 16 after suffering a shock 2-1 defeat to Zimbabwe at Stade Ahmadou Ahidjo.

Kaba Diawara's side started their final Group B match with one foot seemingly in the knockout stage, but Zimbabwe pulled off an upset to end their 14-match winless run in Yaounde on Tuesday.

Captain Knowledge Musona rose unmarked to open the scoring for Zimbabwe - with no chance of qualifying after losing their two other games - after 26 minutes, heading home Never Tigere's cross from six yards out.

Kudakwashe Mahachi doubled Zimbabwe's lead two minutes before half-time, with goalkeeper Aly Keita badly at fault as he failed to keep out the midfielder's shot from outside the penalty area.

Guinea looked a totally different side after the break and Naby Keita halved the deficit four minutes into the second half, bursting forward and unleashing a rasping left-foot strike from outside the box that flew into the far corner of the net.

Zimbabwe came under increasing pressure but held on for their first AFCON win since 2006, while Syli Nationale.will have to wait to learn if they will qualify as one of the best third-placed finishers after Senegal and Malawi drew 0-0 to finish top and second respectively.

Three of the pre-tournament Africa Cup of Nations favourites conclude their group stage fixtures on Tuesday, though one of them is in a tricky situation.

Senegal are on track to qualify from Group B, while Morocco have so far handled the potentially difficult Group C rather well – the same cannot be said for Ghana.

Luckily for the Black Stars, they have arguably – on paper at least – their easiest game of the group stage to look forward to as they bid to avoid falling at the first hurdle for only the second time this century.

Malawi v Senegal (16:00 GMT)

Just by beating Zimbabwe 2-1 thanks to a brace from the excellent Gabadinho Mhango, Malawi have arguably already compounded expectations at this year's tournament.

That was only their second ever win at the AFCON and it ensured they go into Tuesday with a real chance of qualification, either automatically or as one of the four best third-placed teams.

But Senegal still have a lot to play for themselves, with Aliou Cisse's men tied on four points with Guinea.

While that could be enough to take them through anyway, failing to top this group will not be a good look for the team many considered favourites to lift the trophy.

One to watch: Gabadinho Mhango (Malawi)

While Senegal undoubtedly possess the stronger squad, Orlando Pirates striker Mhango really caught the eye last time out with a couple of well-taken goals. One more will make him Malawi's all-time top scorer in the AFCON.

Zimbabwe v Guinea (16:00 GMT)

A wonderful opportunity awaits Guinea here, with the Syli Nationale knowing they will win the group as long as they better Senegal's result.

Their 0-0 draw with the Teranga Lions was a decent outcome and means they are one of just three teams still to concede a goal – though goalkeeper Aly Keita's tournament-best record of 2.4 goals prevented may have something to do with that.

They face a Zimbabwe side with only pride to play for having lost each of their first two games, though the omens are not great for Guinea: the Warriors' only previous AFCON wins have been in their final group matches (in 2004 and 2006).

One to watch: Mohamed Bayo (Guinea)

Despite their chances being worth 2.98 in terms of expected goals (xG), Guinea have only netted once. That 1.98 non-penalty xG underperformance is the second-worst at the tournament. Bayo arrived in Cameroon in good form – they will hope he can inspire an improvement where it matters most.

Gabon v Morocco (19:00 GMT)

As one of only three teams to win both of their first two games this year, Morocco are already assured of a place in the next round – they just need to seal top spot now.

The Atlas Lions are already on their longest unbeaten run at the AFCON (six matches) since going 11 without defeat in the 1970s, and they also boast the best xG (5.3) and xGA (0.5) records of the teams to play twice, evidence of how effective they have been at both ends of the pitch.

But Gabon, who confirmed Pierre-Emerick Aubameyang and Mario Lemina have returned to their clubs for medical reasons, are aiming to go unbeaten in a second success group stage campaign for the first time, with a point likely good enough to send them through.

One to watch: Youssef En-Nesyri (Morocco)

It has been a frustrating season so far for Sevilla striker En-Nesyri, who has missed prolonged periods through injury and then saw his penalty saved against Comoros. His 25-minute cameo then was his first appearance in the tournament. With qualification already assured, they might opt to build up his fitness for the knockouts with a start against Gabon.

Ghana v Comoros (19:00 GMT)

Ghana were held to a 1-1 draw by Gabon last time out, a match that was marred by ugly scenes at full-time after a late equaliser denied them victory. It culminated in a red card for Benjamin Tetteh after he punched an opponent in the face.

Having also lost to Morocco on matchday one, Ghana now need a win to have any hope of progressing – even then, it may not be enough.

If Ghana do not win, it will be the first time they have ever failed to win a single group game in 22 appearances at the tournament.

It would also be their first failure to get out of the group since 2006. Much is at stake.

One to watch: Andre Ayew (Ghana)

While Ghana have some very talented young players in their squad, their qualification hopes are looking a little desperate – they need their experienced stars to take the lead here. Andre Ayew and his brother Jordan are obviously the focus here, given that nine (70 per cent) of Ghana's previous 13 AFCON goals have been scored by the siblings (Andre is on five, Jordan on four).

Burkina Faso clinched a place in the last 16 of the Africa Cup of Nations despite being held to a 1-1 draw by Ethiopia in their Group A finale.

Finalists in 2013, Burkina Faso do not look like threatening to go that far on this evidence, with Ethiopia unfortunate not to claim all three points.

Ethiopia striker Getaneh Kebede saw a bending effort kept out of the top-left corner by Sofiane Ouedraogo in the 10th minute.

They had four shots on target in the first half but it was Burkina Faso who had the only one to find the net, Cyrille Bayala lofting over Teklemariam Shanko after latching on to Adama Guira's superb chipped pass in the 24th minute.

Kebede was then denied again by Ouedraogo from close range, but he eventually got his reward for an impressive performance from the penalty spot.

Steeve Yago was adjudged by the VAR to have handled a free-kick in the area and Kebede coolly stroked into the bottom-left corner from 12 yards seven minutes into the second half.

But the draw proved enough to send Burkina Faso through as Cape Verde – whom they beat in their previous encounter – also drew 1-1 with group winners Cameroon. Ethiopia go home with just a point to their name from only their second AFCON appearance since 1982.

Africa Cup of Nations hosts Cameroon are through to the knockout phase as Group A winners despite being held to a 1-1 draw by Cape Verde, who may well join them in the next round.

Cameroon had already been assured of a place in the knockouts after winning their first two games but they were unable to finish Group A with a spotless record.

It looked like they might when Vincent Aboubakar scored yet again to take his tournament tally to five in three games, the striker finding the bottom-right corner from the edge of the box in the 39th minute.

But the Blue Sharks levelled with what proved to be their only shot of the second half just after the break, and it was a stunner.

Garry Rodrigues met Kenny Rocha Santos' cut-back with a cheeky back-heeled finish past Andre Onana.

That goal keeps Cape Verde's hopes of progression alive – they finish the group behind Cameroon and Burkina Faso but stand a good chance of taking one of the knockout places awarded to the four best third-placed teams.

Pierre-Emerick Aubameyang's Africa Cup of Nations campaign has finished without him even playing a game as Gabon confirmed he was returning to Arsenal for medical reasons.

Aubameyang tested positive for COVID-19 on January 6, ruling him out of Gabon's Group C opener with the Comoros.

Initially he was expected to return to action for the match against Ghana, which finished 1-1, with Aubameyang addressing the media the day before the game after returning a negative coronavirus test result.

But he was held back on medical grounds after the African Football Confederation (CAF) identified "cardiac lesions" – damage or abnormal change to body tissue – in health checks.

While apparently deemed to be not serious, Gabon have determined the best course of action is to send Aubameyang – and Nice midfielder Mario Lemina, who had a similar diagnosis after also contracting COVID-19 – back to his club for the appropriate medical follow-ups.

A statement read: "The Gabonese Football Federation has decided to put the players Pierre-Emerick Aubameyang and Mario Lemina back at the disposition of their clubs in order for them to follow more in-depth exams."

Aubameyang returns to Arsenal with his future at the club unclear.

The striker was stripped of the captaincy in December after reportedly returning late from a trip abroad, and he was subsequently ostracised from the starting XI.

He did not play again before being allowed to leave early for the AFCON, with Mikel Arteta revealing Gabon's request in that regard had been accepted because Aubameyang was not going to play against Manchester City at the start of the month.

Algeria's Africa Cup of Nations title defence hangs in the balance following a 1-0 defeat by Equatorial Guinea.

Esteban Obiang struck 20 minutes from time at Stade omnisport de Douala to lift the National Thunder to second place in Group E.

The result also condemned Algeria to a first defeat in this competition since a 2-1 reverse against Tunisia in 2017, while they must now beat Ivory Coast in their final group game to have any chance of progressing to the knockout stages.

Despite only enjoying 33 per cent of the possession, Equatorial Guinea had the better first-half chances. Oscar Siafa drew a smart save out of Rais M'Bolhi, while Iban Salvador's rasping long-range drive was just wide of the target.

Algeria had the ball in the net at the other end, but Baghdad Bounedjah was denied by the offside flag.

The Desert Warriors continued to dominate possession, but were hit by a 70th-minute sucker punch as a low corner was flicked on by Josete Miranda, before Obiang applied the finishing touch at the far post.

Algeria pushed for the equaliser as the clock ticked down, but were unable to preserve their nine-match unbeaten run at the Africa Cup of Nations and are still seeking their first goal in this year's event.