Gary Neville says it was "not right" for Casemiro and Marcus Rashford to travel to the United States during the international break, given the poor season Manchester United are having, and suggests it might not have been what Ruben Amorim would have wanted.

Neither was called up for their respective countries this month and so decided to travel to Portland to watch an NBA game. Neville has questioned the decision given the toll the long flights and time difference might have had on both players ahead of Amorim's first week at United.

Both were seen in high spirits during the new head coach's first training session at Carrington on Monday - ahead of Sunday's trip to Ipswich Town - but Neville is unsure that they have prepared themselves in the best way given the current context at United.

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"I'd ask the question, would my manager want to see me there, would the fans at this moment in time?" Neville mused. Former United skipper Roy Keane did not see much issue in their travels, though.

He said: "They would have had the international break sorted a couple of weeks ago. I wouldn't be a big fan of it, but I would have thought there was bigger stuff to worry about.

"Don't get me wrong, if they're training in the week and they're looking a bit sluggish... We saw pictures with the new manager coming in smiling, all happy, good PR!"

Neville went on: "The professionalism, looking after your body and making sure you're best prepared for the next training session is critical to every decision you make during the season.

"He [Rashford] has got a mental break - he's got to get away and has got to rest with friends - then you talk about the choice of venue, how far do you fly, what's the time difference, is that going to give a jet lag issue, is that going to give a stiffness issue from being on a flight for 12 hours?

"This is on Casemiro more than Rashford, but if I'm 30-years-old and I'm looking after my body - and he's won five Champions Leagues and is an unbelievable player - but if he was away with Brazil for 10 days, then we would say he could struggle this weekend because he's been away.

"They have chosen that international break, almost. If you are talking about minor details - in being as professional as you can be and as prepared as you can be for a training session on a Monday night - that isn't the best choice of venue."

Neville reckons that he's not overly irked by Casemiro and Rashford's trip, but does not believe either would have had copious amounts of rest time ahead of their return to training. He questioned whether the decision emanated acute "professionalism".

Neville continued: "I'm not that wound up about Rashford and Casemiro going over to the United States, but what I'm asking is; If you've got a four-day break, Portland is a 12-hour flight and an eight-hour time difference...

"Your jet-lag is bad, and you feel a bit [rough].

"They went to Portland and I'm asking the question based on professionalism - you're playing badly, the team are losing, you're 13th in the league, and there is a new manager coming in - would you choose that trip as a break to recharge your batteries? That's not a recharging trip. It's not right, that."