The Scotland international limped out of the Red Devils’ 4-0 win against Real Sociedad at Juventus’ Allianz Stadium, midway through the second-half.
McTominay could now join Paul Pogba in the treatment room with the Frenchman ruled out until March with a thigh injury.
Pogba, 27, has been out of action since the 3-3 draw with Everton at Old Trafford on February 6.
Edinson Cavani and Donny van de Beek did not travel to Italy for the Europa League clash after picking up muscle injuries.
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It is unconfirmed whether they’ll return in time for the visit of Steve Bruce’s men to Old Trafford.
Newcastle, meanwhile, remain without Callum Wilson, Fabian Schar and Javier Manquillo, who are out for a number of weeks.
Bruce could welcome back Federico Fernandez, with a full injury update to follow in his pre-match press conference on Friday morning.