United's latest defeat left them down in seventh place in the Premier League, nine points behind leaders Arsenal, with the club also in danger of not qualifying for the Champions League last 16.

And the Sky Sports pundits both questioned Rashford's performance at St James' Park on Saturday evening when the player consistently failed to track back Newcastle full-back Tino Livramento, with Carragher even comparing the 26-year-old's displays this season with those of his club-mate Martial, who has consistently underwhelmed while at Old Trafford.

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"Watching Marcus Rashford last [Saturday] night that was an unacceptable performance for a few reasons and it is not picking on Rashford as I do not think anyone comes out of it with great credit," Carragher told Sky Sports.

"But that lad didn't play midweek in the Champions League, so there isn't any little mitigating circumstance of why a player hasn't been 100 per cent - playing away from home on a Wednesday night in Europe and then you play Saturday and then the travel.

"But I've been a local player and it isn't easy when you are a local player, especially when your team is not doing well. You have to drag the team up with you, because I'm watching Marcus Rashford now and he reminds me of Martial.

"And that's the worst possible thing you can probably say about him. A foreign player who comes in, hasn't done the business, doesn't care really - and that's a fact with Martial. Marcus Rashford is now looking like Anthony Martial. And if your confidence is down, or you're not scoring goals, or you're not getting assists, that is not a problem. You do not stop running for that badge, shirt, or those supporters."

Keane, meanwhile, claimed United's fans are now starting to become frustrated with Rashford, who was one of the club's best players in Erik ten Hag's debut campaign at the helm last time out - signing a new big-money, five-year deal in July as reward - but who has managed just two goals in all competitions so far this season, one of which was a penalty at Everton the previous weekend.

"What about his body language? The wide players I played with, who were very talented - [Ryan] Giggs, [David] Beckham, [Lee] Sharpe, [Andrei] Kanchelskis, they ran," said the former United captain.

"They ran and they were top players for Man Utd. It's alright running that way [forwards], but you've got to run back. Man Utd's fans don't jump on players' backs that quickly but they're really frustrated with Rashford at the moment. For his lack of skill? Not really. It's because they don't see a player running.

"He's a local lad, he's got a lot of plaudits over the last few years and he's got the mega deal. But you look at players and ask, 'have they got that desire to do well?'

"Marcus isn't showing it that much. Give him a ball to take a penalty [at Everton]? No, I need a bit more. Run forward, no problem, but you run back when you're playing for Man Utd - and no excuses. Every player can have a dip in confidence but you think, 'how do I fix this?' You run.

Carragher and Keane believe Manchester-born Rashford should be setting a better example to his team-mates in this difficult time for the club, with the former Liverpool skipper highlighting Heung-Min Son's tireless display in Tottenham's 3-3 draw at Manchester City on Sunday in comparison.

"There's no tougher place you'll go as a wide player than Man City," said Carragher. "You're not going to get much of a kick.

"Son did not stop running. That was a captain. We're not asking for the goals and assists with Rashford. We've seen that in the past. What you're asking for is leadership. It does not matter who he is playing with, those players should look up to him and say, 'he's Manchester United - he embodies this club'."

Keane called on Rashford to now stand up and be counted

"He's 26. He's not a child anymore," he said. "He's a talented player. If he's one of the senior players - and he's got that huge money - he's got to set the example. Is he on his own? Of course not."