Mancini insisted a "top player" should have scored the sitter squandered by Mario Balotelli that cost the champions dear in a 0-0 draw at West Ham.
Mancini did not pull any punches after the game when asked about Balotelli's miss.
"This is football," he said. "I think that a player like Balotelli, when he has a chance like to today, he should score.
"Because when you are a top player, if you have a chance, you should score this - but I don't think he didn't want to score."