Peterborough United striker Aaron Mclean will undergo an MRI on his knee injury this evening (Friday) to determine the extent of the problem.
Mclean sustained the injury in shooting practice at the end of Monday's training session and as a result, missed the 2-1 defeat to Doncaster Rovers.
Strike partner Liam Dickinson is also set to miss two weeks of action after suffering a hamstring strain during the first half of the defeat.
Posh were dealt a further blow on Friday when centre back Craig Morgan landed awkwardly on his ankle, making him extremely doubtful for the clash at Nottingham Forest.
Lee Frecklington (knee) and Ryan Bennett (groin) are both ruled out, but Chris Whelpdale and Kerrea Gilbert have been added to the squad.
Manager Jim Gannon said: 'It is a real blow to lose so many players due to injuries, but we will give it a good go. Losing Craig in training was a disappointment because we were just doing some work on set-pieces and he just seemed to stumble.
'Aaron will have a MRI to reveal the extent of his injury while Liam will be out for around two weeks. It is not a pull or anything but he has got a little tear,' Gannon said.
