Van Persie hit the winner in yesterday's derby just months after snubbing City for United.
“The player shooting was Van Persie and he shot very well. I called Carlos to return to the wall, but I was too far away on the bench," said Mancini.
“Van Persie scores against every team and once United signed Van Persie they improved a lot. But we have four great strikers and we can win the title again this year."