What will prove to be intriguing in Utah is whether Mourinho persists with a 3-5-2.
'Today he was in a different team than Lukaku.
Will Zlatan stay at Manchester United?
Fireworks were followed by ticker tape at the kick-off - paper that was still floating to the ground when Jesse Lingard snatched possession, allowing Rashford to finish smartly after 115 seconds. United were totally in control at this point in the game and the Galaxy were struggling to keep any sort of possession.
The 3-0 scoreline reflected United's dominance in the opening half an hour, and they nearly scored a fourth shortly after Fellaini's strike when Lingard's curling shot landed on the roof of the net.
A move back to United, whom he left for a then world record £80m in 2009, has been mentioned as a possibility.
Zlatan spent one successful season at Manchester United but is not fit again until December at the earliest. They went up against a lineup that included the ex-Chelsea player Ashley Cole.
Manchester United strolled to an emphatic win vs LA Galaxy in the opening game of their U.S. tour - as new signings Romelu Lukaku and Victor Lindelof made their debuts.
'So obviously in the second half they had players with more experience, better quality, and were more hard to beat.
But Lukaku, who replaced the young England striker at half-time when United changed their entire starting line-up, missed a wonderful chance to get off the mark within four minutes of coming on and scuffed another opportunity wide. The Armenian attacker slotted it past the helpless goalkeeper.
"He didn't score goals, but he played better than the ones who did score goals..." said the United manger on the Belgian's performance.
The complete change of personnel at the interval didn't stem the tide either, with Matteo Darmian and Timothy Fosu-Mensah able to abandon all defensive duties and attack the flanks.
United won big but not can be drawn from this match.
According to the Sun, Real are ready to bid £50 million for Red Devils goalkeeper, David de Gea.