Will Addison and Marty Moore are doubts for Ulster's do-or-die Heineken Champions Cup pool showdown with Bath this weekend.
Full-back Addison injured his calf during last Saturday's 29-13 defeat to Clermont Auvergne.
Prop Moore is also battling to be fit; he's currently nursing an ankle knock. Utility back Matt Faddes is definitely out after sustaining a shoulder injury.
Dan McFarland's men will qualify for the last eight if they turn over Bath at Kingspan Stadium.
Any manner of victory will do, though they would progress as pool winners if they earned a bonus-point win and Clermont lost at Harlequins.