Leinster will be without Rhys Ruddock for between four and six weeks due to a calf injury.
The back row suffered the injury in the first half of last weekend's Champions Cup defeat to La Rochelle and looks set to miss a sizeable chunk of the province's Rainbow Cup campaign which continues against Connacht at The Sportsground this Saturday (LIVE on eir sport 1 from 7.15pm).
The Ireland international, who has shown some excellent form this season, joins a growing injury list which includes captain Jonathan Sexton, Caelan Doris and Harry Byrne.
Sexton is unlikely to be fit for the trip to Galway as he continues his recovery from a head injury, while Doris is doubtful after suffering a calf strain in the warm-up ahead of the defeat to Munster in round one.
Byrne faces another three or four weeks on the sidelines as he recovers from a hamstring injury sustained early on in the game against Munster.
Scrum-half Jamison Gibson-Park and utility back Jimmy O’Brien are close to a return, but Will Connors (knee), Jack Dunne (ankle), Adam Byrne (quad), Dan Leavy (knee), Conor O’Brien (knee) and Max Deegan (knee) remain sidelined.
See EIGHT Rainbow Cup games LIVE only on eir sport this weekend.