The Argentinian, signed for a British-record £59.7m during the summer, is recovering from a pelvic injury.
Winger Adnan Januzaj (illness) and midfielder Ander Herrera (muscle problem) have also trained this week and may return to the starting XI for the match at the Britannia Stadium.
"Herrera has trained today for the first time with us and Januzaj has also trained two training sessions with us," United manager Louis van Gaal said yesterday.
"They don't have match rhythm. Januzaj was ill and you have to recover from your illness, not from your tiredness. Maybe it's worse to recover from illness."
For United's full injury list, click through the gallery below...
Marcos Rojo (thigh), Daley Blind (knee) and Marouane Fellaini (rib) are likely to miss out, however.
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