Nottingham Forest frontman Nathan Tyson is facing up to a month on the sidelines with a calf injury.
The pacey forward picked up the problem during training last week and missed Sunday's 1-1 draw at Cardiff as a result.
It had been hoped that he would be able to shake off the complaint in time to feature against Bristol City on Saturday.
However, he is now set to be out of action for the foreseeable future, joining fellow strikers Dexter Blackstock and Robert Earnshaw in the City Ground treatment room.
"It is a massive blow to lose Nathan for a month," said Reds boss Billy Davies.
"To lose the pace of Tyson and the goal scoring of Tyson, along with Blackstock and Earnshaw, means we have got key players missing from the squad.
"As I have said before, top teams can't afford to lose important players.
"The Bristol City game on Saturday might come too early for Dexter Blackstock, while Earnshaw is probably looking at Middlesbrough after the international break."