Former Manchester United boss Sir Alex Ferguson admits he sometimes failed to control his temper during games.

The BBC's upcoming documentary, 'Sir Alex Ferguson: Secrets of Success,' will be aired at 10.30pm on October 11.

“I always wanted to get it off my chest, out of my system and kick on from there," said Ferguson. “What I said to them remained in the dressing-room.

“I could be really angry, I could be volatile, but then it was over, and the players knew that. I never brought it up again and I never held a grudge, ever in my life.

“Sometimes I would lose my temper when we'd won. The real reason for losing your temper is because of expectation. I could never envisage us losing a game.

“By the time I'd picked my team, done my tactics, given my team talk, I was confident we'd always win the game.

"But, of course, you don't win every game, that's a fact. But when they dropped below their expectation, that annoyed me most, you know."