Sir Alex Ferguson has described the criticism of Arsene Wenger by Arsenal fans as "ridiculous" and questioned whether the club will "ever get another manager like that".
The Frenchman, whose contract runs out at the end of the season following 21 years with the club, is yet to announce his future intentions at the Emirates Stadium.
Fan protests against Wenger have grown in recent months following a somewhat disappointing season for the club, which could still end on a relative high with victory in the FA Cup final over Chelsea at the end of the month.
Former Manchester United boss Ferguson, who went head to head with Wenger for 17 years in the Premier League before retiring in 2013, questions whether Arsenal know what they really have in the veteran manager.
He is quoted by Sky Sports News as saying: "At the moment, of course, with the ridiculous situation of the pressure Arsene is under, I just wonder if they realise the job he's done.
"The most amazing thing about him is this - he has come through a forest of criticism for months now, and has never bowed. He has seen it right through, he has shown a determination, a stubbornness. I think when you look at that, it's a quality, and I'm not sure they'll ever get another manager like that.
"It's quite easy to say 'Get rid of him', but who do you get? Who do you get in to keep that club the way they are for the next 20 years? I really feel sorry for him because I think he's shown outstanding qualities, and I think he has handled the whole situation. I don't know many that have done that."
Arsenal are still battling to keep their impressive record of qualifying for the Champions League in each of Wenger's full seasons in charge, requiring victory over Everton on Sunday and other results to go their way.