Marcus Rashford does not know “the process of being a substitute”, says Paul Ince, with the Manchester United forward seeing his “mindset” questioned after suffering an injury scare.
The England international was named on the bench for an FA Cup third round replay with Wolves on Wednesday.
Ole Gunnar Solskjaer took the decision to introduce the 22-year-old just past the hour mark in that contest.
Rashford lasted only 16 minutes before being forced from the field with a back complaint.
Solskjaer admits that a calculated gamble on a player who was also withdrawn against Norwich “backfired”, with the Red Devils now sweating on the fitness of a key man ahead of a trip to Liverpool on Sunday.
Ince has suggested that United should have better prepared Rashford for a role against Wolves, on what was a chilly January night at Old Trafford.
“He’s more or less started every game. I don’t think he’s used to being a substitute,” Ince told BT Sport.
“I don't think he knows the process of being a substitute …how vigorously you warm up, do the right things. Do you think you’re going to get on the pitch? So it’s kind of a mindset where you think ‘well hopefully I’m not going to get on’.
“All of a sudden he’s thrust into the action because they need a goal.
“He is a talisman, he is the main man, and 16 minutes down he’s getting dragged off again with a bad back which hopefully he’ll be ok for the Liverpool game.”
He added: “I think it was actually something he picked up in the Manchester City game where he got a bit of a knock on his back.
“But he played the Norwich game, was excellent Saturday so this was an opportunity for him to have a break.
“Ok it didn’t quite work out, he had to come on because United were struggling.
“I think he’ll be ok, he walked off alright and maybe a bit of ice, couple of days rest, he’ll be fine for Sunday.”
United found a match-winner against Wolves shortly after Rashford’s introduction, as Juan Mata netted the only goal of the game, but a place in round four of the FA Cup may have come at a price.