Rashford reported ill for training on Friday, and consequently missed the trip to south Wales.
United initially defended videos of Rashford in a nightclub in Belfast, Northern Ireland.
The club claimed Rashford was free to do what he likes in his own time, as they said the video was from Wednesday night and before a scheduled day off.
However, further videos surfaced of Rashford going to a nightclub on Thursday night and he was absent from training on Friday.
Following the win against Newport, Ten Hag said the issue was an ‘internal matter’.
‘So he reported ill, for the rest it’s an internal matter,’ said Ten Hag.
‘I deal with it. As I said, it’s an internal matter.’
Rashford was photographed driving into United’s Carrington training ground on Monday morning, alongside a host of other players.
It would appear to confirm that the forward is over the illness that kept him out of the weekend’s action.
United take on Wolves at Molineux on Thursday when they return to Premier League action.
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