Villa have been the worst side in the Premier League by some distance this campaign, and they have been destined to be relegated for a prolonged period of time.
The Claret and Blues have shown a lack of fight - and they have won just three matches all season.
Villa are currently a staggering 21 points away from safety, but Merson rates Allardyce as a manager so highly that he believes he would have kept the Midlands club in the top tier.
“I think he’s different class,” Merson said. “He’s up there with the best of the best. If he was manager at Aston Villa they would have stayed up. It’s as simple as that. He doesn’t play into the fans’ hands, he knows the league. I can’t talk highly enough of the man.”
Allardyce has never before been relegated as a manager, and that proud record has remained in tact this season, against the odds.
When Allardyce took over at Sunderland they looked to be one of the favourites for the drop.
However, the 61-year-old boss has done a remarkable job at the Stadium and masterminded a great escape.
Sunderland confirmed their survival on Wednesday evening with a win over Everton, condemning Newcastle United and Norwich City to relegation with Villa.