Jose Mourinho took his escalating feud with Chelsea manager Antonio Conte to a new level on Friday night.
The Manchester United boss hit back during his post-match press conference after Conte suggested he was becoming 'senile' earlier in the day.
He should have been discussing how late goals from Jesse Lingard and Romelu Lukaku had guided his side into the FA Cup's fourth round after a tough tie against Championship promotion-chasers Derby.
Instead when asked about Conte's comments, he bit.
The Chelsea manager's own barb had come because he thought Mourinho had accused him of acting like a clown on the touchline, and the United manager said: 'Look, I don't blame him (for the reaction), honestly I don't blame him.