Manchester City boss Pep Guardiola believes a 24-hour dedication to football that includes early morning gym sessions is behind Ruben Dias' magnificent start to life at the Etihad Stadium.

Dias became City's record signing when he joined for £62million from Benfica in September, arriving in the immediate aftermath of a humbling 5-2 Premier League defeat against Leicester City.

Since then, the Portugal international has done plenty to justify his price tag, establishing a formidable partnership at centre-back alongside a rejuvenated John Stones.

Across 13 Premier League matches with Dias in the side, City have been beaten only once, conceding seven times at an average of 0.5 per game. In the two matches before his signing, City conceded six - largely as a result of the Leicester debacle, in which they gave away three penalties.

Dias leads the way among his team-mates in clearances (55) and headed clearances (27) this season. He is behind only Rodri (31) and Joao Cancelo (25) when it comes to interceptions, having made 20.

Spain holding midfielder Rodri has 50 aerials won to his name, with Dias next up on 37. City's new defensive lynchpin is also yet to make an error leading to a shot in the top flight.

Having burnished his growing reputation with fine displays in the wins at Chelsea and Manchester United over the past week, Dias is expected to sit out Sunday's FA Cup third-round tie against Championship strugglers Birmingham, but Guardiola insists he would have no problem turning out once again.

"Do you know when the player makes a big sign or an influence on the team? When he is able to play every three days. That is the best signing," he said.

"When you buy players, always you think they will help the squad but you never know what is going to happen. He is a guy who can play every three days and recover immediately.

"His ability is incredible. He understands the game, he wants to learn and all of us are impressed by how much he takes care of his body and his mind.

"The day after [the game] at 8:30 or 9:00 he is in the gym, he makes his routine perfectly. He lives 24 hours of his profession at 23 years old.

"I can assure you that we signed an incredible player for the next five, six or seven years and that is not easy to find."

City's improvement at the back has also been a collective endeavour.

Along with Stones putting form and fitness woes behind him, versatile full-back Joao Cancelo has blossomed in his second season under Guardiola, while Oleksandr Zinchenko recently returned to plug a gap at left-back amid a raft of COVID-19 cases among his team-mates.

The manager believes City's collective play was never too far away from the standards set of late, with the drive to cut out individual errors key.

"I have the feeling that always we concede few, few chances in the previous seasons," Guardiola said.

"It was more in actions that we didn't control individually, we made mistakes. For example, the three penalties against Leicester are mistakes we cannot make.

"We improved in those terms. The movements of the collective are the same as the last five years but the mistakes we have done against Leicester, conceding three penalties, we have not done it again."

A handling mistake by Ederson in October's 1-1 draw at Leeds United is the only error City have made leading directly to a goal in the Premier League this season, according to Opta. In 2019-20, they made seven across the course of the campaign and six when amassing 100 points as champions in 2017-18.

"A part of this, of course, is Ruben helps us a lot to lead the line and John doing what he is doing," Guardiola added. "When he has played, Nathan Ake has played good, Ayme [Aymeric Laporte] as well.

 "Joao has made a step forward - we knew his quality with the ball, but especially without.

"We have to continue. The margin between being solid and not being solid is so minimal. We have to be careful and continue to be consistent in the next month."