Boro will head for Millwall on Saturday without the services of defender Ryan Fredericks while Aitor Karanka has two further injury doubts ahead of the game.
Fredericks limped out of Saturday's 1-1 draw with Blackburn Rovers with a thigh injury and the on-loan Tottenham youngster could be set for a month on the sidelines.
Centre-back Dani Ayala also left the field following a clash of heads while goalkeeper Dimi Konstantopoulos sustained a hip injury when he appeared to be taken out of the game during the build-up to Blackburn's 95th minute equaliser.
"Ryan could be four weeks," confirmed Karanka. "Both Dani and Dimi are doubts for the weekend."
Tomas Mejias has been the unused substitute goalkeeper in recent weeks, but the last time Dimi missed out, it was Chelsea youngster Jamal Blackman who stepped into the breach, for the Capital One Cup trip to Liverpool in September.