Former Chelsea and Manchester United manager Jose Mourinho said Kurt Zouma’s indiscipline caused the foul which led to United taking a first-half lead against the Blues at Old Trafford.
The French centre-half had a nervy opening 45 minutes typified by the challenge which saw him bring down Marcus Rashford, who scored the resulting penalty.
“I would be very frustrated with Zouma,” Mourinho said on Sky Sports.
”You analyse opponents and that is one basic thing when you play against Marcus Rashford.
“In that position he always goes for the inside, he goes to look for his favourite foot, his favourite position and his favourite shot.
“When you are in the box you just have to close the inside and not put your leg out.”
An earlier mistake by Zouma almost led to a United goal before they eventually took the lead.
Zouma’s ball across the face of his own box, intended for Jorginho, drifted straight to Anthony Martial, who shot straight at keeper Kepa.
It was a fortunate escape for the centre-back, who was later booked.