Manchester United manager Jose Mourinho was left to rue a poor defensive performance with his return to Chelsea on Sunday ending in a 4-0 defeat.

Antonio Conte’s side was ruthless in attack and took the lead within the opening minute as Pedro, once linked with a move to Manchester United, took advantage of some calamitous defending from England international Chris Smalling.

‘If you can delete the defensive mistakes from the game I would say it was a good performance,’ Mourinho told MUTV after the match.

‘Class performance, good possession, using the ball well, creating chances, creating half chances, pushing the opposition to a defensive approach and I would say obviously a very, very, very unfair result.

‘But we cannot delete the mistakes from the game and the first mistake happened after 30 seconds. Then we had a completely different game because Chelsea’s best quality is playing counter-attacking football, and especially in the second half when we were very close to making it 2-1, they punished us on the counter-attack.

‘When we were close to 3-1, they punished us on the counter-attack again, and we were close to 4-1 with Zlatan and Marcos Rojo’s shots. Probably with a few more minutes they would score again. Everything went wrong from minute one. After that, everything was against us in the game.’

Trailing 2-0 at the break away from home, Mourinho admits that by instructing his side to chase goals it played directly into his former side’s hands.

‘I spoke with the players in a very honest way at half-time. I told them we had to try, because in the end, to lose 2-0 or 3-0, 4-0 or 5-0, in terms of points, it’s the same.

‘It’s not the same in terms of feelings, but in terms of points it is the same. I was very honest with them and I told them that we have to try, and we are going to try, but we have a risk, because now this is what Chelsea wants.

‘Chelsea wants to defend and then to go on the counter-attack. If we score, they are in trouble, but we have a risk, and then we had chances to score – we didn’t – they go there, they score and they kill the game.’

Mourinho and Manchester United will have little time to lick their wounds as they welcome Manchester City to Old Trafford for the EFL Cup on Wednesday.

The match kicks off at 21:00.