Connacht hooker Jason Harris-Wright may face up to six months out with a shoulder injury.
The 25-year-old dislocated his shoulder against the Blues last weekend and will see a surgeon today to discover the extent of the injury.
Willie Faloon will also miss Saturday’s game against Ospreys (Liberty Stadium, 6.30pm) after the flanker picked up a hamstring strain in last Friday's captain's run.
London Irish-bound centre Eoin Griffin sustained a shoulder injury in the last outing and will continue to be monitored ahead of Friday's team announcement.
Meanwhile, Mick Kearney, Kieran Marmion and Darragh Leader, who all picked up knocks or cramps on Saturday, have trained well and are available for selection.
Nathan White, Tiernan O'Halloran and Paul O'Donohoe remain unavailable through injury.
Elsewhere, Munster captain Peter O’Mahony, who will be out of action until October, has had keyhole surgery on his second shoulder.
Already recovering from surgery on a shoulder injury suffered against Toulouse in the Heineken Cup, it was decided to operate on the right shoulder during the rehab.
Coach Rob Penney said: “He has had ongoing issues for a long time with the shoulders so he is getting both of them tidied up.”