Sunderland boss Gus Poyet admitted his side could have no complaints about the manner of their 4-1 defeat to Manchester City on Wednesday.
The Black Cats took the lead early through Connor Wickham, but Poyet rued his side's inability to hold it for more than two minutes before Sergio Aguero equalised.
"Sergio is unique and at this moment in time he is one of the top three on-form strikers," Poyet said. "He has performed week in, week out whether it is against us or Bayern Munich and it shows.
"I can't have too many complaints -- they were better than us in every aspect of the game. We started well and had a chance before we scored our goal, but then Aguero appears from nowhere and does something special."
Poyet said his side's gruelling fixture schedule told against City, coming so soon after a gutsy goalless draw against Chelsea at the weekend.
He added: "It's hard on us to play these two games consecutively and the physical demands were a lot.
"We thought before the game we would be on the same level and we would be able to compete - but we were not."
Information from Press Association was used in this report.