The 25-year-old was a big summer signing for the Red Devils, moving from Chelsea in a deal worth up to £60m, but his spell at Old Trafford has been almost entirely forgettable so far.
The England international has made just four Premier League starts and four more substitute appearances after being struck down by hamstring and then calf injuries.
Mount remains sidelined, although he has returned to training on the grass and his return may not be too far away.
Ten Hag has sympathy for the former Blues man, but is keen not to rush him back into action, hoping that he can get back to his best and still make a big impact at the club.
‘He was struggling from the second game of the season,’ said Ten Hag. ‘He returns for a period and then picked up another injury, so of course that’s not great.
‘That is very frustrating for him and I really feel for him, so I really want to be there for him because he had such high expectations – and I had high expectations.
‘I’m sure he [will be] a very good player for us. But first of all – and we have to do it very securely – is to get him fit.
‘Secure in the process – step by step, don’t force it – and then hopefully, by the end of the season, he can stay fit and find himself in the team – or at least he plays a role in this team.’
The Red Devils host West Ham on Sunday in the Premier League and Ten Hag confirmed that Lisandro Martinez is available, but Tyrell Malacia is out and Victor Lindelof is a doubt.
‘Ty and Mason Mount I don’t expect them back, but I think Victor Lindelof is almost back,’ he said.
‘Yesterday he trained with the team and we have to see how far he is.’
For more stories like this, check our sport page.
Follow Metro Sport for the latest news on
Facebook, Twitter and Instagram.