David Moyes' first prestige signing when he replaced Sir Alex Ferguson as manager, the combative Belgian has either been a hard-working and committed squad player with an impressive mentality, or a sub-standard and clumsy recruit who was never really United quality.
After getting the second goal though, United took their foot of the pedal and that allowed the hosts to gain confidence and they should have got a goal back when Ghayas Zahid was unmarked in the box but from a few yards out, he blasted the ball over the bar when he really should have scored.
Despite being a favourite with his current boss, the 29-year-old has struggled to win over a sceptical fan base since making a £27.5 million switch to Old Trafford.
The Belgian midfielder has been strongly linked with a move to Galatasaray in recent days.
Galatasaray's sporting director, Cenk Ergun, has revealed they are "close" to a deal to acquire Marouane Fellaini from Manchester United.
Matic knows how Mourinho likes to play and knows what is wanted of him so bedding-in time will not be an issue - meaning that United are to be treated to a newer Paul Pogba this season.
Just minutes into the second half, Lukaku thumped home a powerful header to double the visitors' lead, and in doing so confirmed another strength of his which will make United more risky as the game goes on this season - aerial ability.
Anthony Martial might have made it 3-0 in the 52nd minute after meeting a brilliant cross from Fosu-Mensah, but the Frenchman could only head over the crossbar during a spell of of sustained pressure from the Red Devils.
This could be a sad day for the Premier League.
It was 3-0 to the visitors with 20 minutes remaining as McTominay found a smart finish to find the net.
No sooner had Manchester United touched back down on British soil than they were back on their back on their travels once more as their gruelling pre-season continued.