Marouane Fellaini took advantage of a goalkeeping howler as Manchester United overcame a wobble to win 2-1 at Crystal Palace and close in on Champions League qualification.
The Belgian midfielder guided into an empty net 12 minutes from time after Julian Speroni failed to deal with Ashley Young’s cross.
The Red Devils had missed their previous two spot-kicks and had not scored in three matches until the Spaniard coolly converted from 12 yards after Scott Dann was adjudged to have handled Young’s centre.
The result means United end a run of three straight defeats and are now seven points clear of fifth-placed Liverpool. They will qualify for next season’s Champions League if the Merseysiders lose at champions Chelsea on Sunday.
Van Gaal had been deprived of Angel Di Maria (training injury) and Robin van Persie (virus) in the lead up to the game and they suffered more injury woe when Luke Shaw was carried off on a stretcher following a first-half head injury.
Wayne Rooney also picked up a knock and did not return for a barnstorming second half which saw David De Gea produce two astonishing saves to keep out Glenn Murray.
The impressive Puncheon also had a big penalty shout turned down when Mata appeared to clip him in the area, but Palace could not snare the second equaliser their performance probably deserved and they are left to lament Speroni’s moment of madness.