"Every time they attacked, they could have scored".
With confidence growing from that moment, Arsenal seized control and spurned a few chances to extend their lead before Aaron Ramsey latched on to a Mesut Ozil through-ball to make it 2-0 on the stroke of half-time.
Arsenal have four players missing for tonight's game.
He has transformed their season since replacing the sacked Vincenzo Montella in November, leading them on a 13-match unbeaten run and giving them faint hope of climbing into Serie A's European qualification places.
It was the first goal Milan had conceded in 599 minutes and they should really have been punished further, with Danny Welbeck shooting straight at Donnarumma one-on-one and Mkhitaryan clipping the crossbar with the goal at his mercy.
Some might see the reigning World Cup-winning manager as an ideal target to succeed Wenger if he leaves, but Low's contract commitments and any reluctance to leave Germany may place him beyond Arsenal's reach.
First legs like this always have the potential to be dour, defensive affairs - Milan hasn't lost since December and hasn't given up many goals in the process, and Arsenal struggle to score in the best of situations, so this game could easily end up 0-0.
When asked why Arsenal were so much better than they have been lately, Wenger said the two losses to City - in the Carabao Cup final and the Premier League - had also had an impact on the Brighton game. The Italians had gone 10 games without losing between these defeats.
With five goals and nine assists this season, Ozil has had a hand in more goals than any other Arsenal player.