Martinez has been out since September due to a foot injury, while Casemiro last played on 1 September as he has a hamstring issue.
Both the Argentinian and the Brazilian were expected to be back in action this month, and that could still be the case, but Ten Hag has made no guarantees of that.
The Red Devils boss says it could still be weeks for the defender and the midfielder to make the ‘next steps’ towards a return, after training on the grass fora number of days already.
‘They are a long time already back on the grass and now they return back into team training but not fully, so partial,’ Ten Hag told a press conference ahead of an FA Cup tie against Wigan on Monday night.
‘Now they have to make the next steps and that may take some days, I think even weeks.’
Manchester United still have a long list of injuries, but the likes of Luke Shaw, Tyrell Malacia, Victor Lindelof, Harry Maguire and Anthony Martial are all thought to be back for the Premier League meeting with Tottenham on 14 January.
Rasmus Hojlund is due to be back even sooner and is set to be involved on Monday at Wigan after recovering from the illness that kept him out of the defeat to Nottingham Forest last time out.
‘He will return,’ said Ten Hag. ‘He dropped out shortly before the game [against Forest] and so he was a little bit unwell before the game.
‘The day before we expected him to play and then he dropped out shortly before the game but he is back in training.’
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