MANCHESTER, England -- Pep Guardiola has challenged the big names left out of Manchester City's 2-1 victory over Sunderland to convince him they deserve a place in his squad.
Yaya Toure, Samir Nasri, Wilfried Bony and Eliaquim Mangala were among those left out Guardiola's 18-man squad for the Catalan coach's first game in charge on Saturday.
England keeper Joe Hart was also left on the bench -- with reserve keeper Willy Caballero starting in goal -- casting further doubts over the future of the City No. 1.
Guardiola doesn't expect any of his players to be happy about his decision but insists there is an opportunity for them to fight their way back into his plans.
Asked how Hart reacted to being told he wasn't playing, Guardiola told a news conference: "I'm pretty sure he's not happy."
He added: "A lot of players were not on the list. All the players that didn't play, they are sad they are absent, of course. I would not like them to be happy that they did not play.
"I'm sorry but I have to decide. We have 28 players and a lot of players injured like [Ilkay] Gundogan, like Samir like many, many players.
"They have to convince me on the pitch -- it's the only way."
Guardiola insisted his lineup was based purely on a tactical decision rather than anything personal. And he said he expects the players who were left out to react positively and battle for a place in his squad.
"I have no doubts about that," he said. "I know Yaya from Barcelona -- how much he loves to play football. I know perfectly his quality.
"He knows the reason why he wasn't on the list because I speak sometimes with the players and say the reason why.
"I know they are so professional I saw it. In maybe one-and-a-half months together, there wasn't any training sessions they didn't show me how good and professional players they are. Every day was amazing.
"But after I sit and decide what is best for me. But it's not a personal problem about any player."
Full-back Aleksandar Kolarov was a surprise starter at centre-half against Sunderland partly because Nicolas Otamendi has a slight tendon injury.
However, the Argentine could be back for Tuesday's crucial Champions League playoff first leg with Steaua Bucharest.
"Hopefully he can play. I'm looking for that, because Steaua, they tell me, play a long, long ball, and of course Nico is so important," Guardiola said.
"He had a little bit [of] a problem in the tendon and he could not risk to play two games in three days and that's why I decide to play with John [Stones] and Kolarov."
Guardiola claims his preference for Willy Caballero at the weekend was more down to the fact the Argentinian began preseason training earlier than Hart and is therefore more familiar with the new system.
Guardiola said: "Maybe the next game it changes, maybe not. I needed the build-up and to use the goalkeeper to play quicker to arrive the balls behind the line. Willy had this quality first of all, he trained more times. He arrived on the first day.
"That doesn't mean Joe can't do that. I know the quality of Joe, he is an amazing goalkeeper. He plays for the national team and he was so important for the two Premier League (title) wins. The personality, the character, I know about.''