Iain Henderson and Luke Marshall both suffered injuries during the final round match in Rome and will miss Ulster's trip to Edinburgh.
Henderson, who came on as a first half replacement, sustained a foot injury and will be assessed later today. Starting centre Luke Marshall suffered a concussion against Italy and will be monitored over the next seven days.
Ulster are currently second in the RaboDirect PRO12 table, level on points with leaders Glasgow Warriors going into the round 18 fixtures.
ULSTER Squad (v Edinburgh) - Backs (11): Ricky Andrew, Jared Payne, Michael Allen, Paul Marshall, Peter Nelson, Michael Heaney, Paddy Jackson, Stuart Olding, Darren Cave, Andrew Trimble, Niall O'Connor.
Forwards (14): Neil McComb, Callum Black, John Afoa, Robbie Diack, Mike McComish, Dan Tuohy, Lewis Stevenson, Johann Muller, Nick Williams, Rob Herring, Niall Annett, Ricky Lutton, Tom Court, Nigel Brady.