- Premier League
Mancini losing patience with Balotelli
But despite slipping six points behind their rivals and seeing their 37-match unbeaten home league run come to an end, the Manchester City manager declared his team can win both the Premier League and the FA Cup.
"I am sure we can win the double this year," said Mancini, who was heartened by his team's comeback from 2-0 down before Robin van Persie's injury-time winner. "We showed we can win the title again this year. This season is a long one."
However, the Italian believed Balotelli, who was a surprise selection to start, let him down before the striker was substituted and stormed off down the tunnel.
"When you have a player with the quality Mario has, you can't understand why he continues to throw his quality out of the window," Mancini added. "It is incredible. In my life, I saw a player with fantastic quality who did nothing. I don't want Mario to finish like him. He can't continue to play like today. We wanted more from him. He has everything [but did not do enough]."
The City manager also blamed Samir Nasri, who deflected in Van Persie's free-kick. City had three men in the wall but Mancini, referring to the Frenchman, said: "Two and a half."
Mancini was also annoyed that Carlos Tevez, who he had hoped would be a fourth man in the wall, had left it but he could not get his message through to the Argentine amid the noise at the Etihad Stadium. "I called Carlos to return to the wall," he said.
The 48-year-old rued United's two first-half goals, scored after City started the stronger, and said: "For 20 minutes they didn't touch the ball and the first chance they got they scored a goal. We recovered very well and we dominated the second half.
"We wanted to win the game and we had chances. We have showed we are a really strong team. We didn't deserve to lose this game. We played very well."