#3 Lukaku as a wide forward

Even though the Belgian faded away in the second half, Arsenal had no reply to his position as a wide forward in the first half. A little better composure and passing from the Belgian could have killed the game early in the second half, but in truth, he had already sealed the deal before the break.
Lukaku started on the wide right position, contrary to the expectations. Solskjaer preferred to have Lingard running through the middle, creating nuisance as usual. Due to the Belgian's position, Koscielny had to shift a little to stop the gap created due to the overlapping Kolasinac.
This opened up spaces for Lingard to run into and caused a few problems for the Gunners. But it was Lukaku's position which actually helped United take a two-goal lead.
The Belgian first set up Sanchez in the 31st minute, cutting inside from the right and laying a gorgeous through ball when the whole world expected him to shoot. Two minutes later, he ran down the right and picked up Lingard, who had a simple tap in to put United two goals up.