Although Antonio Valencia's early strike and Jesse Lingard's brace ultimately secured a first win for United at the Emirates Stadium since 2014, De Gea's significant contribution can not be overlooked as the no.1 was in outstanding form between the sticks - beaten only by Alexandre Lacazette's strike early in the second half.
That they didn't was a result of bad first 10 minutes, during which two defensive errors led to United goals.
"I loved the way my team played and fought".
There was controversy to be found, of course, with Arsenal having a pretty reasonable penalty shout denied in the game's later stages but perhaps the biggest scandal on the night was the sending off of United's Paul Pogba, who - as a result of his misdemeanour - will miss out on his side's crucial derby matchup with Manchester City next time around.
"You know - if you are my friends, don't ask me the question, because you know I get into problems".
But Arsenal are three points closer to the runaway Premier League leaders - and Wenger reckons this crushing defeat will just make his side even more determined to catch up.
"If it was hard, no; if it was mud, no - the pitch is absolutely attractive but I think they were a bit too much".
'But we have the experience to get better out of a game like that, you know. I am here to fight as long as I can, as long as mathematically it's possible you have to fight.
"We played well but there is nothing more frustrating when you have that quality of performance and nothing to show for it at the end". And we put ourselves in a very hard position.
"I didn't see the tackle", Mourinho said.
"We are second in the table".
After that David De Gea kept them at bay with a goalkeeping masterclass which included a Premier League record-equalling 14 saves, until Lacazette gave them hope. Although Alexandre Lacazette pulled one back, Jesse Lingard netted a third for United. "What I saw was the best goalkeeper in the world".
"Despite being 2-0 down we should have come back - we had enough chances", said Wenger, whose side are now fifth.