Yorke fears Wayne Rooney could turn his back on a new £300,000-a-week contract at United if Moyes fails to secure Champions League football next season.
The Premier League champions are hoping to tie their leading scorer down to a record-breaking four-and-a-half-year deal – and are increasingly confident he will commit his future to Old Trafford.
Yorke says it is imperative United make a statement by holding onto the 28-year-old, who is out of contract at the end of next season.
But the 1999 Treble-winner admits that he would bide his time if he were in Rooney’s shoes.
With United languishing in seventh place and already out of both domestic cup competitions, Yorke believes Rooney may want to weigh up his options at the end of the season.
“I think Wayne Rooney will have to sit and sort of look at the situation,” he said. “I think if I was Wayne Rooney that’s exactly what I would be doing because I don’t want to be in a Man United team that has been deemed the worst Man United team – or we are not challenging and playing in Champions League football next year.
“He can’t afford to do that. He is running out of time. He is at that certain age now when he needs Champions League football even more than before.”
United’s hopes of convincing Rooney to stay at Old Trafford for the remainder of his career look far more positive than they did last summer.
Back then the England striker seemed certain to depart after Sir Alex Ferguson claimed he had asked to leave.
But despite attempts from Chelsea and Arsenal to lure him to London, Moyes insisted he was not for sale and has since helped him rediscover his best form.
“I go back to what I’ve said earlier on in the season that I don’t think he would leave,” Yorke added. “But if he were to leave this time around simply because of results or the changes he’s seen at the football club, he doesn’t really like, that would show a sign of weakness.
“I don’t think the club could really afford for him to go. Because you are letting your star player go and yet you are trying to get star people in. it just doesn’t add up.
“The size of Man United – you can only do that. With no disrespect to likes of Aston Villa or Everton, when you let your star player go to a bigger club that’s just the norm.
“You don’t let your star players go from a football club that is struggling and then expect to attract big name players to the club it just doesn’t happen.
“I am sure the board and everybody – and David Moyes will know this. They simply can’t afford to let Rooney leave the football club at any cost.
“He’s been one of our sparkles apart from Adnan Januzaj. Really he’s been our main man this year.”
