The Gunners boss took his Arsenal team to Old Trafford for the final time ahead of his exit at the end of the 2017-18 season.
Arsenal appeared to have rescued a point after Henrikh Mkhitaryan cancelled out Paul Pogba’s opener at the Theatre of Dream.
However, Marouane Fellaini scored a 91st-minute winner to deny Wenger a point on his final visit to Old Trafford.
Manchester United are in second place in the Premier League table and four spots above Arsenal following the Gunners’ disappointing campaign.
Writing in his personal blog One Hour Behind, Mata paid a touching tribute to Wenger ahead of the Arsenal boss standing down at the end of the season.
“These three points were very good for us, in a game that was the last one of Arsène Wenger as the Arsenal manager at Old Trafford,” Mata wrote.
“In 22 seasons he’s been through everything in this stadium and I think that at the end the football world is showing to him the affection that he deserves. A lot of things have changed with him in the Premier League, he was an innovator and it’s fair to admit that he has contributed so many things to English football, and to thank him for that.”
Arsenal haven’t won the Premier League title since 2003-04 when Thierry Henry and Patrick Vieira inspired the Gunners to an unbeaten season.
The Gunners signed Borussia Dortmund striker Pierre-Emerick Aubameyang and Manchester United midfielder Henrikh Mkhitaryan in the January transfer window.
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