Vincent Kompany welcomed the competition for his place from new signing Nicolas Otamendi as he argued Manchester City's superb start to the season has been motivated by the knowledge that they will lose their spots in the side if they are not right at the top of their game.
City captain Kompany feels manager Manuel Pellegrini has so many high-class options in his squad that they know they cannot afford to slip up in training, let alone in matches.
The Belgian has scored twice and helped City keep three clean sheets in their 100 percent beginning to the campaign but faces a fight to stay in the side after the Premier League leaders paid £31.5 million to bring in Valencia centre-back Otamendi.
City can also call upon an in-form Eliaquim Mangala, plus the promising youngster Jason Denayer and Martin Demichelis, who was their best centre-back last season.
And Kompany said: "Competition is one of the reasons we have started so strong. You can't really afford to do anything wrong during the week leading up to the game. Then during the game, you can't do anything wrong either as there is always someone looking over your shoulder, waiting, who is just as good as you.
"If they are in a better moment and they deserve a chance, they will take your place. You have got to be at the top of your game. This is what you are seeing -- a group of guys who know that they need to perform. If they don't, someone else will do it."
Kompany welcomed City's decision to bring in Otamendi, who Pellegrini has described as arguably the best centre-back in La Liga last season.
"It is so important in any top team to have quality players all over," he said. "The extra competition is good, really good. You don't play for a top team unless you have that.
"If you look at the schedule, you could end up with 50 or 60 games and that is impossible for one team. If you want to go for every trophy, we have got Denayer, Demichelis, Otamendi, Mangala and myself. You need that to go for it."
Kompany was criticised for his own form last season but is pleased with his performances in the current campaign and is determined to remain at the top of his game.
"It shows on the pitch that I feel good and I feel happy with myself," he said. "I am 29. Things are coming easier. I just don't want to miss any opportunities to have a good game or have a good season. Every game counts for me. This when I need to perform."