The Black Cats gave their hopes of survival a boost with a win over Norwich on Saturday.
The Black Cats are currently 18th in the table and a point from safety, having beaten Norwich City in a crucial relegation scrap in Saturday’s early kick off.
If they are relegated, they are arguably the best equipped of the current bottom three, alongside Aston Villa and Newcastle United, to make an immediate return to the Premier League.
Their hopes though, rest firmly on if they can keep hold of Sam Allardyce, who is an expert at getting teams out of the Championship having managed it with West Ham United.
And as far as Merson is concerned, it is a must that they keep hold of Big Sam this summer if they are relegated.
“I think if Sunderland, Newcastle and Aston Villa go down, I’d fancy Sunderland to come back up,” he told Sky Sports Soccer Saturday.
“I don’t see him going, I’d be shocked if he left. He’s been there a long time, so for me I think he stays. It’s not like Benitez where you come in and if it doesn’t work out then see you later.”
“There’s no better in my opinion if you want to get out of the Championship. He’ll recruit the right players to get you out of trouble. They must make him stay.”
For now, Sunderland must simply focus on trying their utmost to avoid the drop this season.
Crucial to their hopes is getting striker Jermain Defoe back among the goals as the season draws to its end.
He is their top goalscorer this season, but had struggled for goals in recent weeks before his strike against the Canaries and they will be hoping that is the first of several more.