Milan cast aside their north London counterparts with ease at San Siro, with the Gunners already being written off ahead of the second leg.
However, the 67-year-old was not getting too carried away by the extent of the result, and proceeded to single out striker Robin Van Persie as a target for praise.
He told Sky Sport Italia: "Perhaps the victory was facilitated somewhat by the inferiority of Arsenal, but I saw a fantastic player for Arsenal in Robin van Persie, who I like very much and forced [Christian] Abbiati into making two decisive saves.
"I just like good football. I follow English football and Van Persie, I believe, is a fantastic player."
Galliani also believes the victory was even more memorable when taking into account the lengthy list of names currently on the treatment table.
"4-0 is a good result, but we could have scored even more," he continued. "It was a perfect game, but we knew that we were still recovering from several injuries."
Arsenal have the task of overturning their four-goal handicap at the Emirates Stadium on March 6.
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