Ulster are counting the physical cost of their Heineken Cup quarter-final defeat to Saracens with six players sidelined following the 17-15 defeat.
Ulster, currently third in RaboDirect Pro12, played for the majority of the quarter-final at Ravenhill with 14 men after Jared Payne was sent off.
However, they subsequently lost fly-half Ruan Pienaar, hooker Rory Best, lock Dan Tuohy, number eight Roger Wilson and wing Andrew Trimble to injuries.
Pienaar suffered a recurrence of a shoulder injury that will keep him out of action for up to six weeks while Best sustained what Ulster says is a 'significant ankle sprain' and will be sidelined for as much as two months.
Tuohy will undergo surgery this week to repair a fractured hand and Wilson has a broken thumb.
Trimble was concussed during the game and will follow return-to-play protocols and prop John Afoa has a back injury, meaning he will miss the Pro12 clash with Connacht on Friday (11th April).
Ulster's remaining games this season are against Connacht, Glasgow, Leinster and Munster and they are currently on course for a play-off place.