Mourinho blames 'incredible defensive mistakes' for United defeat.
Jose Mourinho says his side's "incredible defensive mistakes" was the reason for Manchester United's 4-0 defeat to Chelsea at Stamford Bridge.
The Portuguese returned to play the west London side for the first time since he left in December 2015.
Pedro broke the deadlock just 30 seconds into the game and Gary Cahill made it 2-0 in the 21st minute as Antonio Conte's Blues went into half-time with a comfortable lead.
Eden Hazard and N'Golo Kante dribbled past Chris Smalling to make it 4-0, however, Mourinho said the early goal changed the match.
"The first minute you analyse the goal and you see immediately what happened. We made incredible defensive mistakes. Individual defensive mistakes and you pay for that," he told Sky Sports.
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"If you equalise or score the 2-1 after the 2-0 you have a big chance because in terms of football the team was quite comfortable.
"With a strategy you cannot [let the opponent] score in the first minute and after that, the game changed completely. [The gameplan] goes out of the window, but we were coming to have an offensive approach.
"We wanted to create chances, we wanted to score goals. We showed that immediately after the 1-0 when we had chances and positions. I think at the end [Thibaut] Courtois had more saves than [David] De Gea.
"I told the players we should take the risk in the second half knowing they are very good on the counter-attack, but if we scored a goal like we almost did the game could be completely different, but it's one of those days where we give the advantage to the opponent.
"They were winning 2-0 after 20-25 minutes. After that they played well, they were defensively compact and they used what they possess best, which is the counter-attack.
"In the second half we played with [Marcus] Rashford through the middle to create more mobility from Zlatan's [Ibrahimovic] position.
"We played with two midfield players we had no problems at all, we had control of the game, but the control is a bit dangerous because Chelsea has great players on the counter-attack and they were just waiting for that."
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