Hull City midfielder Jake Livermore picked up an injury on the training ground.
Livermore picked up a knee injury and he was forced to sit out of Hull’s match against Milton Keynes Dons.
The Tigers missed the central midfielder’s presence against MK Dons, and they could only pick up a 1-1 draw against the relegation strugglers.
That was a blow to Bruce’s side’s promotion chances, and it seems that they could be without Livermore again in midweek.
"Unfortunately Jake tweaked a knee yesterday in training,” he said.
"We don't know who's going to be available on Tuesday (to play Forest) but thankfully Jake is not a horrendous one. I think it's 50-50.”
Livermore has been a key player for Hull this term, with his performances catching the eye in the heart of midfield.
Hull’s draw with MK Dons has left them third place in the Championship table and they will be under pressure to get back to winning ways on Tuesday against a struggling Forest side.
The Reds have won just one of their last six matches and they parted company with manager Dougie Freedman earlier today.
Forest are now set to be managed by first-team coach Paul Williams at the KC Stadium.