The Red Devils recently announced that the 23-year-old will be training away from the side amid a 'squad discipline issue'.
Sancho hit out at Ten Hag after the Dutchman's comments about his level of training, with the former not part of the squad that lost to Arsenal.
He took to social media after the 3-1 defeat in a now-deleted post and claimed that he was a 'scapegoat', as well as refusing to apologise to the United boss.
The winger was spotted watching the Under-18s at their Carrington training ground last week, with a return to action not yet clear.
Amid Sancho's situation, a report from the Manchester Evening News claims that some United players are beginning to 'grow weary' of Ten Hag's criticism.
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They have lost four of their opening six matches of the season and dressing room sources told the outlet that some players believe he has 'favourites' and won't criticise them, whereas he will for others.
Ten Hag's tactics have also come into question as some in the squad feel as though the absence of Antony, who is addressing allegations of domestic abuse, is affecting his approach.
"Everyone can make suggestions, we are okay with it. At United, you have to win every game so it doesn't change anything. As always, it's about how we play against Burnley, there's no easy game, definitely not against Burnley."
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talkSPORT's chief football correspondent Alex Crook has been left less than impressed with such leaks as he took to X to say: "Certain United players really are gutless.
"Easier to pin the blame on yet another manager than admit their own shortcomings. Don't need to be a detective to work out where the leak is either. Cry me a river."
He added: "I'm not saying Ten Hag is perfect by the way but this is a repetitive cycle and the common denominator is not the man in the dugout."
United kicked off the season with a 1-0 win over Wolves, although their performance was far from convincing.
They avenged a 2-0 defeat to Tottenham with a 3-2 victory over Nottingham Forest, but they have lost every game since.
Defeat away at Arsenal was followed up by losing 3-1 to Brighton at Old Trafford, leaving United 13th in the Premier League.
They had the chance to make amends in the Champions League on Wednesday, but it was Bayern Munich who emerged as 4-3 victors in Germany.