It needed a fine save from Hart to deny Lukaku a quick second after a swift break involving Sanchez, but the Belgium striker smashed home from point-blank range to make it 2-0 before half-time after Lingard’s shot hit first Charlie Taylor and then Ashley Westwood.
Paul Pogba wasted the chance to make it 3-0 when Hart comfortably saved his rather tame penalty, and Burnley hopes of a comeback were increased two minutes later when substitute Rashford was sent off for pushing his head into Phil Bardsley’s after he appeared to kick out at the forward.
Sean Dyche’s men pushed forward with the man advantage but Lukaku should have killed off the game, the forward wasting two opportunities when put clean through one-on-one with Hart.
United held firm for their second win of the season, though, allowing Mourinho to head into the two-week international break in a happier mood.
But this was a start and an important one. Burnley are a little meek this season but after United’s troubles against Tottenham and previously Brighton this game still resembled a hurdle to negotiate, a test of commitment and mental toughness as much as their football.
MATCH FACTS AND STATS
BURNLEY (4-4-1-1) Hart 8; Bardsley 6, Mee 5.5, Tarkowski 6, Taylor 5.5; Lennon 6, Cork 6, Westwood 6, McNeil 6 (Barnes 80mins 6; Hendrick 6 (Vokes 57mins 5.5); Wood 5.5 (Vydra 83mins 6)
Not used: Heaton, Lowton, Ward, Long
BOOKED: McNeill, Bardsley
MANAGER: Sean Dyche: 6
MANCHESTER UNITED: (4-3-2-1): De Gea 6.5; Valencia 6.5, Smalling 7, Lindelof 7, Shaw 7.5; Fellaini 6.5, Matic 6.5, Pogba 6 (Bailly 90mins 6); Sanchez 8.5 (Rashford 61mins 4), Lingard 7.5 (Herrera 75mins 6); Lukaku 7.5.
Not used: Grant, Martial, Fred, Young.
GOALS: : Lukaku 27, 44
BOOKED: Sanchez, Shaw, Lukaku
SENT OFF: Rashford
MANAGER: Jose Mourinho 8
REFEREE: Jonathan Moss 7.5
MAN OF THE MATCH: Alexis Sanchez.