A fourth-placed finish in the Premier League is the best Manchester United can hope for this season, so says Ralf Rangnick.

United have dropped to fifth following successive draws with Burnley and Southampton, which came off the back of an FA Cup exit at the hands of Middlesbrough.

The Red Devils can move above West Ham into the Champions League places, however, should they win their game in hand against Brighton and Hove Albion on Tuesday.

But United trail third-place Chelsea by seven points, while Liverpool and Manchester City are 14 and 23 points better off respectively.

Ahead of hosting Brighton at Old Trafford, Rangnick conceded that his side cannot currently consider challenging for anything other than securing the final Champions League place.

"Right now, this is exactly what Manchester United needs and wants: to finish fourth in the league," he said at Monday's pre-match news conference. 

"I think this is the highest possible achievement we can get domestically. In the league, it's number four, that's our ambition, what we have to achieve and what we're aiming at."

Rangnick was appointed as interim manager until the end of the season in November and is set to take on a consultancy role from the end of the season for two years.

"After being here for 10 or 11 weeks, I know what we need next season," Rangnick added. "But it's not the time now to discuss this with anyone.

"My full focus is on tomorrow, then Sunday, Wednesday and the next couple of weeks.

"My focus is on the current squad, getting the best out of this season and then, after that, it's time to speak about the next steps for next season and the next couple of years."

After failing to win after being ahead at the interval in four of their last six matches in all competitions, Rangnick knows his side are lacking in confidence.

"It's obvious if you are 1-0 up in 11 out of 13 games and win half, and in three consecutive games you concede an equaliser, then it affects the minds of the players," he said.

"They think they should be 2-0 up or 3-0 up and it's 1-1 – it affects the players. We have to be more effective to score the second and third goal and kill the game off. 

"But if it doesn't happen then we have to be disciplined. You can understand that it affects the confidence of the players. 

"The only thing we can do is speak to the players one by one and explain to them why."

United's issues have been laid bare by their profligacy in front of goal since Rangnick replaced Ole Gunnar Solskjaer. Since his first game in charge on December 5, they have scored 17 goals in all competitions, but their expected goals (xG) figure is 23.3.

That differential of -6.3 is the third-largest among all teams in Europe's top-five leagues in that time, behind only Lyon (-8) and Rayo Vallecano (-7.4).

Rather than focus on his misfiring attackers, though, Rangnick believes United need to tighten up at the other end.

"It's clear the players are getting it. It started with [the FA Cup win over] Aston Villa and since then the players feel and understand the job," he said. 

"They now need to do it sustainably. The first half over the last couple of weeks has been very good. We didn't concede a single goal. 

"The next step is to raise our level physically, tactically, mentally. It's been too easy for other teams [to score] and also our own mistakes that we made let the other teams score."

Asked if his players are to blame for the ongoing three-match winless run, Rangnick said: "I don't know. 

"It is something to discuss at the end of the season. The players are ambitious and want to get better. They want to win. My job is to help them and show them a pathway."

United have won their last five Premier League games against Brighton, this following a run of three games without a victory in the fixture.