That’s the opinion of former Red Devils defender David May.
He believes United are in talks with both players in order to make sure they are at Old Trafford for the prime of their career.
“The club are in talks with David and he’s happy where he is,” he told 888sport.
“With Martial I’m sure they’re sorting out figures as well.
“Neither player are in the prime yet with David just approaching his and he is the best goalkeeper in the world.
“So you have to ask yourselves if he goes and he needs replacing, then how much would that cost to replace him?
“So you’re better off paying David £300,000-a-week or whatever he wants to keep him at the club for the next five years.
“If it just comes down to money then give him what he wants.
“The same goes for Anthony Martial who is a terrific player.”
May also believes Manchester United should hand the manager’s job permanently to Ole Gunnar Solskjaer.
The Norwegian has won his first give matches since replacing Jose Mourinho in the dugout.
He explained: “Personally I’d love to see Ole get the job. I’ve known him for twenty years and I know that he loves the club so much. He also knows what the club is all about.”
“Ole has done an unbelievable job, he really has. He’s transformed somewhere that was all doom and gloom into a dressing room that you can see is now enjoying their football.
“People go on about his record down at Cardiff but no disrespect to them but we’re talking about two very different teams and very different clubs.
“United is a massive job, of course it is, but if you don’t give him a chance you won’t know where he might get them to.
“He’s got them playing the right way and getting results so why not?”
United return to action on Sunday when they take on Tottenham in the Premier League (4.30pm).