Jose Mourinho feels the referee made "a crucial mistake" which proved decisive in Manchester United’s derby defeat against Manchester City on Sunday afternoon.

The Reds claimed for a penalty in the 79th minute when Ander Herrera went down under the challenge of Nicolas Otamendi but match official Michael Oliver chose to book the Spaniard for simulation and City went on to win 2-1 at Old Trafford.

Here are the manager's main comments from his interview with Sky Sports and post-match press conference:

“Clear penalty. I'm sorry for us, I'm sorry for Michael [Oliver, the referee]; I think he had a good performance but it's a clear penalty. The referee made a mistake, which can happen. Last season we had a similar situation here against Man City - City were winning 2-1 and [the referee] Mr [Mark] Clattenburg didn't see the penalty, [Claudio] Bravo on [Wayne] Rooney, and this one also. It's a clear penalty and I feel sorry for Mr Oliver because he had a good performance. He's a human being and tried his best; he was very committed to having a good match, which I think he had. He made one mistake, which was a crucial mistake for the result of the match. You can speak about anything you want. You can bring any football theory, you can bring the stats, the ball possession, you can bring everything you want, but like last season it is a huge penalty in the crucual moment of the game. But I also have to say I feel sorry for Michael Oliver because he had a good game, a very good game. The assistants the same. I think [Jon] Moss [the fourth official] came with the intention to make the perfect work which they almost did."