Wayne Rooney's first return to Old Trafford since leaving Manchester United in the close-season ultimately ended in a 4-0 thumping thanks to three late goals, as Romelu Lukaku scored against former side Everton to heap the pressure on Ronald Koeman.
United were poor for much of Sunday's Premier League match, but blew Everton away in the final stages, with Rooney - who previously missed a couple of good chances - powerless to help following his substitution, with Henrikh Mkhitaryan, Romelu Lukaku and Anthony Martial all netting after the 82nd minute to condemn Everton to a fourth successive defeat in all competitions.
Unsurprisingly, most of the pre-match attention was on Rooney and Lukaku, but within four minutes of kick-off Antonio Valencia had successfully made himself the man of the moment with a simply spectacular 20-yard strike.
Everton did improve as the first period went on, with Rooney squandering a decent chance, but United remained the bigger threat and Lukaku should have scored two separate occasions.
United were poor after the break, however, with their attacks becoming predictable and slow, while David de Gea twice bailed them out when denying Rooney and Gylfi Sigurdsson.
But in the final seven minutes United came to life once again to punish Koeman and Everton, as Lukaku set up Mkhitaryan, scored himself and then saw Martial fire home a penalty, extending Everton's winless run to six games in all competitions to further increase the scrutiny on Koeman.