Premier League icon Alan Shearer has issued a stark warning to Manchester United forward Marcus Rashford.

The MEN reported this morning that Barcelona are considering two options for the England international as he faces an uncertain future at Old Trafford. Hansi Flick's side are hesitant over a January loan move for the 27-year-old but would be open to signing the forward this summer.

New United head coach Ruben Amorim has been hard in his stance on Rashford but speaking ahead of their Europa League showdown with FCSB, offered an avenue back into the first-team picture - if he makes the changes he is demanding.

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Shearer has offered a reminder to Rashford of the opportunity in front of him and warns that he can't afford to waste it.

"I think Ruben Amorim has been pretty clear and what he has said is perhaps what other managers before him couldn't say or didn't want to say about Marcus Rashford," said the 54-year-old speaking to Betfair.

"He's been brutally open and brutally honest, 'this is the situation, this is what I've inherited, and I'm not accepting it. You either jump into my boat and row with me or you're not getting it at all', and I think that's a great attitude to have from the manager. It's the only way to go.

"I like Amorim's openness, and I like his honesty, and I probably think previous managers are looking at that situation he's got with Marcus and thinking, 'yeah, that's what we had also, but you're now telling everyone how it is.'

"It's a tricky situation because of the wages that Rashford will be on. You've got to understand the situation and the magnitude of what you're taking on and who you're taking on.

"Three years ago, this guy could phone the Prime Minister up and sit in front of them, yet now he can't even get anywhere near the first team at Man United.

"I hope he gets it right, and I hope he realises what he's doing. The opportunities are passing him by. He's at one of the biggest clubs in the world and I hope that he and his people are looking at things and thinking 'are we doing the right thing?'"