Inter Milan legend Marco Materazzi saw Chelsea defeat Manchester United in Monday's FA Cup clash.
The Italian remains close to United boss Jose Mourinho and scoffs at claims the former Inter coach is 'past it'.
"I went to London to see Chelsea-Manchester United in the FA Cup, a great game that made me laugh. The Blues have more quality than United, but in both cases you are seeing the hand of the coach," he told TMW.
"Look, I was sitting two rows behind their benches. I can tell you that I'd never to have wanted to be that fourth official!
"Jose is Jose, he has not changed."