Mancini 'worried' about Aguero
Aguero fell awkwardly following an early challenge by Nathaniel Clyne. It was quickly obvious the Argentina forward was in some considerable pain and although he indicated a desire to continue, medical staff quickly decided the damage to his knee would make it impossible.
Mancini confirmed it will be 48 hours before City can make a proper diagnosis. However, as with all such injuries, the fear Aguero may have damaged his cruciate ligaments is obvious.
"I am worried," said Mancini. "We don't know how serious it is because we need to wait maybe two days for the scan. But usually the knee is dangerous. The injury was so strange because it was not a bad tackle. It was not strong.
"The good thing was that he wanted to try and play. But at the moment we can't say anything."
Mancini conceded that if the worst is confirmed later this week and Aguero is ruled out for an extended period, he may have to change his squad building plans.
He is still hoping to bring in a new face, with strong rumours linking him with Roma midfielder Daniele De Rossi, although Mancini said he knew nothing of any developments.
"If it is a serious injury we will probably change our plans," said Mancini.
"But we need to wait. Maybe it will be one week or three or four weeks, after the international break."
Mancini also confirmed the complete absence of Adam Johnson from his matchday squad was to give the winger an opportunity to look for another club.
Johnson was at the Etihad Stadium this afternoon and trained with a number of team-mates after the match had finished.
However, he has become tired of being a bit-part player with the Blues, although Mancini insisted he has no axe to grind against Johnson, who started England's midweek win over Italy in Berne.
"Adam is a young guy," said Mancini. "He is a good player and he wants to play. In these 10 days, if we find a good solution for him and he can go to play, maybe it is better. I don't know about a loan. We have two or three situations. We are talking with him about this. But if he stays here I don't have a problem."