Wayne Rooney spotted Marcus Rashford training alone at Carrington last Sunday, having been excluded from Manchester United's travelling squad to Fulham.

And the Red Devils icon, who was taking his children to their match at the club's training ground, branded the moment "embarrassing" as uncertainty over Rashford's future rumbles on.

Ruben Amorim omitted the 27-year-old from the group that won 1-0 at Craven Cottage, the 11th success game in which he hasn't featured.

Rashford last played in the 2-1 victory at Viktoria Plzen on December 12 before a lengthy exile his head coach has put down to training attitude and application.

His absence will extend to 12 matches in Thursday's Europa League curtain-closer against FCSB after not flying to Bucharest.

And on the latest episode of Stick to Football, Rooney offered insight into Rashford's routine when his team-mates travel for games without him.

"I went into Carrington on Sunday to take my kids to game day, and Marcus Rashford was out on the training pitch with the fitness coach," the recently sacked Plymouth Argyle manager explained.

"But he was right over towards where the parents were walking past for the kids' games. I looked at him, thinking how embarrassing it must be for him as parents walk past."

He added: “I was surprised when [Marcus Rashford’s training issues] started over two years ago, but now I’m not.

"I've spoken to Marcus a couple of times, and I've given him my thoughts and feelings that he needs to leave the football club because whatever is going on in his life and at Manchester United, he's not the same.

"For him to have a fresh start, he needs to leave the club. The fact that your manager is coming out and saying that you're not training right is crazy."

Roy Keane weighed in and didn't hold back when expressing his disappointment in how Rashford's United career is stumbling to a sour end.

"I can't get involved in the conversation. I still can't understand at any level - whatever's going on with players leaving, months left on contracts - a player who doesn't train properly," Keane said.

"I don't understand it; you might as well leave me out of this conversation. Especially if you think he wants to move, which is more of a reason to train properly.

"So when you go to a new club, you're up to speed, and when you leave the club, at least you showed a decent attitude. He must be ashamed."

Ian Wright, who has been one of Rashford's more supportive ex-players in recent years, also couldn't hide his frustration with the England international.

He stated: "The whole situation with Marcus Rashford is sad – how it started for him and now where we are. If your manager says that about you, about work ethic and training...

"Even if he wants to leave, which he obviously does, surely there are people watching how you're performing – he should still be on the bench.

"Going into training and working is down to you as a professional, whether you're at United or elsewhere. That's on Marcus and if that's happening, it's sad to hear."

With just five days of the January transfer window remaining, the clock is ticking for Rashford to find an escape route before the February 3 deadline.

Amorim insists he wants to use the United No. 10 but has maintained that setting standards to guide the club out of its rut is more important.