Sir Alex Ferguson claims Arsenal's fans should be "ashamed" for the way they treated Arsene Wenger in the latter part of his tenure.
The Frenchman led the Gunners for over two decades after taking charge in the mid-1990s.
He was the first man to consistently challenge Manchester United's dominance of the Premier League, winning three league titles in seven seasons as well as several FA Cups.
Even when they weren't challenging for the title Wenger still ensured Arsenal remained regulars in the Champions League.
Since the 72-year-old's departure the Gunners have not returned to the top table of European football with Ferguson highlighting their achievements despite labelling them "dinosaurs".
The Scot said in the new film, Arsene Wenger: Invincible: "He kept them in Europe every year and yet he was criticised. The supporters should be ashamed.
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"Arsene and myself are dinosaurs, but we didn’t do so badly.
"I won 13 leagues but I was never near going through a season undefeated. The achievement stands above everything else, and it was Arsene’s."
Wenger has never returned to the Emirates since leaving his post in 2018.
Arsenal have had two managers since him with Mikel Arteta now at the helm.
Discontent among fans came as results nosedived during Wenger's reign with a banner famously telling the Frenchman it was time to go.
The Frenchman, now in a role with FIFA, admits the anger from supporters did impact him because it tarnished the image he wanted to give off.
"I am not resentful of fans, I just feel if my personality is in the way of what I feel our club is, for me that is more important," Wenger said.
"But I believe this club is respected all over the world, much more than in England.
"Our fans did not give the image of unity I want at the club all over the world – that was hurtful."
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Wenger has conceded that he should've left long before he eventually did with 2007 pinpointed as a key time.
David Dein left the club as tensions grew in the boardroom and upon reflection the former Arsenal boss believes a departure may have been favourable with offers a plenty during his career.
"I identified myself completely with the club - that was the mistake I made," he told the Telegraph.
"My fatal flaw is I love too much where I am... where I was. I regret it. I should have gone somewhere else."
