And Wenger, who host Milan at the Emirates next Thursday, was pleased with his side's response to their nightmare run of form. "And that's what we have shown, we needed to find mental resources".
"When you are knocked down like a boxer, you don't have time to react and you are only halfway up, but you have to respond. That's what we did tonight", Wenger told a news conference.
"Overall, it is important to win, but it is not qualification".
Hakan Calhanoglu perhaps could have won a penalty had he chose to go to ground after beating David Ospina to the ball, and Gattuso must have wished he had when the Gunners broke the deadlock. Ozil played a fine pass into Ramsey's path and the Wales midfielder rounded Donnarumma for an easy finish.
Milan were slightly better after the break but never truly threatened to reduce the deficit.
Giacomo Bonaventura scooped a shot over when he should have done better, while Suso drilled a left-footed strike out for a throw-in.
Arsene Wenger uses boxer analogy to describe Arsenal's nightmare run of form
"The second leg will be hard to turn this around, but anything can happen in football".
Kosovo global Valon Berisha scored twice shortly after half-time to put Salzburg in control, the first from the penalty spot, and leave German giants Dortmund facing a surprise exit.
Here are five things we learned from the 2-0 victory.
Spanish worldwide Costa has now scored six goals for Atletico since returning to the club from Chelsea in January.
The Gunners look to be in need of change and are facing the prospect of ending a season trophy-less for the second time in three campaigns-the UEFA Europa League is their last chance at winning a title this term.
E-cigarette use exposes teenagers to toxic chemicals says new study
Hess said there are countless other studies that prove vaping is 95 percent safer than smoking traditional cigarettes. E-cigarettes, or vape pens, consolidate seasoned liquid and nicotine to convey a less unforgiving type of smoking.