McTominay is the first of Man United's Euro 2024 players to be back in training, and the Scotland international is expected to be involved against the Gers this weekend.
Harry Maguire could also feature, with the centre-back making strong progress in his recovery from the muscular issue that saw him miss the end of last season and also Euro 2024.
Andre Onana, Victor Lindelof, Amad Diallo and Antony were left out of the squad for Monday's 1-0 defeat to Rosenborg, but all four could be involved this weekend.
Aaron Wan-Bissaka, Jonny Evans, Casemiro, Mason Mount and Marcus Rashford started against Rosenborg, but the former might not feature here, as he is being heavily linked with West Ham United.
Jadon Sancho has patched-up his differences with head coach Erik ten Hag and could be included in the squad, but new signing Joshua Zirkzee is still on a break following his involvement in Euro 2024 for Netherlands, so the striker will not make his debut here.
Altay Bayindir, Diogo Dalot, Christian Eriksen, Bruno Fernandes, Rasmus Hojlund, Kobbie Mainoo, Luke Shaw, Lisandro Martinez, Alejandro Garnacho and Facundo Pellistri remain unavailable due to international commitments at Euro 2024 and the Copa America.
As a result, there will again be opportunities for youngsters to impress, with Habeeb Ogunneye, Harry Amass and Ethan Wheatley potentially among the starters on Saturday afternoon.
Manchester United possible starting lineup: Onana; Ogunneye, Fish, Evans, Amass; Casemiro, Mount, McTominay; Antony, Wheatley, Rashford