Uche Ikpeazu and Peter Haring will be assessed ahead of the William Hill Scottish Cup semi-final against Inverness at Hampden Park on Saturday.
The Hearts striker and midfielder picked up knee and groin injuries respectively during the 2-1 home defeat to Edinburgh rivals Hibernian in the Ladbrokes Premiership at Tynecastle at the weekend.
Full-backs Ben Garuccio and Demetri Mitchell and forward Steven Naismith are all out with knee injuries.
Christophe Berra said: "Everyone naturally will see us as favourites because we are in the top league.
"But these games are always difficult. Even in the previous rounds, when we played against Partick Thistle, we found it difficult ourselves. So they are no mugs.
"Our form has been a bit up and down so we know that on the day we need to perform and if not it is going to be a tough day."
Predicted squad
Provisional squad:
*Zlamal,
*Smith,
*Godinho,
*Brandon,
*Berra,
*Souttar,
*Shaughnessy,
*Mulraney,
*Bozanic,
*Djoum,
*Lee,
*Clare,
*Haring,
*Ikpeazu,
*Morrison,
*Wighton,
*MacLean,
*Vanecek,
*Keena,
*Doyle.
