Soccer:Manchester City manager Roberto Mancini is threatening to leave Mario Balotelli out of his side's crucial Premier League clash with Chelsea at Stamford Bridge. Mancini appears to have lost patience with the Italian striker in he wake of his Europa League red card against Dynamo Kiev last night.

Mancini claimed the latest controversy to erupt around the young Italian cost City a place in the quarter-finals after he had watched his remaining 10 men battle for almost an hour to overhaul Dynamo Kiev’s first-leg advantage.

In the end, the Blues fell just short, with many fans pinning the blame on Balotelli, who was sent off for a ridiculous studs-first challenge on Goran Popov.

Balotelli remains a popular figure within the City dressing room but Nigel de Jong — embroiled in his own controversy following the World Cup final — admits the striker must start to heed a few lessons.

“He is a young boy of 20 and he has to learn from his mistakes,” said the Dutch international. “I told him. Everyone told him. He is still part of the squad and has a lot of potential. He is a very good player but has to realise, on a professional level, you sometimes have to change your mentality.”

De Jong will certainly be around to offer his own experiences as a guide and is sure his team-mates will rally round as well in a bid to smooth the rough edges from Balotelli’s game that are hindering his undoubted talent.

“We are there to help him, not to criticise him or blast him away,” he said. “He is still a young lad and has to learn. But he has experienced guys around him and has to listen to them. After the game he was angry and he was disappointed”