Pep Guardiola believes Manchester City, Liverpool and the other Premier League heavyweights are pushing one another on to higher levels in the manner of tennis greats Rafael Nadal, Roger Federer and Novak Djokovic.

City beat West Ham 4-0 on Saturday and are unbeaten after 13 games of their title defence, with 35 points on the board.

Normally, such a return would see them established as runaway leaders but Liverpool's hard-fought 3-0 win at Watford means Jurgen Klopp's side are only two points off the summit.

Chelsea were also undefeated heading into the weekend before being taken apart 3-1 by Tottenham at Wembley, who themselves have 30 points.

Guardiola overcame West Ham counterpart and City predecessor Manuel Pellegrini at London Stadium, a coach with whom he enjoyed a memorable battle in LaLiga.

Pellegrini led Real Madrid to their then-record points haul of 96 in the 2009-10 season, only for Guardiola's Barca to pip them to the title with 99.

Asked whether a similar battle for supremacy is likely in England this term, the City manager drew parallels with the heights three of the finest tennis players in history have propelled one another towards.

"I remember perfectly that season, how tough it was. Madrid with Manuel played incredibly good," he said.

"It was so nice because we did those 99 points when the year before we won the treble with Barcelona. To maintain that level… we did 99 points with someone else pushing us. We knew that if we dropped points Madrid were going to win the title.

"It's similar with Nadal, Federer and Djokovic, no? They push one to be better than the other one because they know.

"We need it in sport, as athletes. They [the City players] know. I didn't tell them, but they know how strong Liverpool are.

"They know that we can't drop points because if we do Liverpool are going to win the league. I can say Liverpool or Chelsea and Tottenham are the same in this moment. Arsenal as well.

"To compete we need good opponents close and this season we have it, here and in Europe."

Guardiola praised his team's collective work rate – a selfless spirit perhaps best exemplified by the dependable contributions of Fabian Delph.

The 29-year-old captained England for the first time against the United States this month, an outing he followed with arguably his best performance in national colours as Gareth Southgate's men dramatically beat Croatia to seal a spot in the Nations League finals.

At West Ham, career midfielder Delph returned to the left-back position he filled in accomplished fashion for City last season, with first-choice Benjamin Mendy set for another extended spell on the sidelines.

"First of all, he is a nice guy," said Guardiola. "You cannot do that – be captain, play one position, play another one and help the team if you are not a good guy.

"He's an important player with us. Last season he helped us a lot playing in that position when Mendy was injured. He did it again well.

"I know it's not easy when you don't play in that position for a long time. The minimum [fighting for the team] always has to be there and Fabian always is a guarantee in this kind of issue."