Cillian Willis will be out for the rest of the season following shoulder reconstruction. The Leinster scrumhalf underwent the operation on Monday.

It is a big setback for the 21-year-old, who broke into the Leinster set-up this season and acquitted himself superbly, particularly in the Heineken European Cup match against Gloucester at Lansdowne Road.

Willis was called upon following injuries to Guy Easterby and Chris Whitaker and certainly embraced the challenge.

He made his senior debut in a Magners Celtic League game away to Borders and then his European bow the following week against Gloucester.

Willis has been extremely unlucky with injuries over the past couple of years. Last season he picked up three hamstring injuries in succession, limiting his appearances at provincial level to a few A matches. And having worked assiduously on rehabilitation, he then incurred shin splints during the summer.

Michael Cheika confirmed Willis would not play again this season.

"He had an operation on Monday and will be out until the end of the season," said the Leinster head coach. "The doctor had a look at it (the shoulder) and thought it was unstable.

"The surgeon said the best course of action was to operate now. He's a long-term prospect for us and we have confidence in him for the future so we have to make sure that we do the right thing . . . It's a big disappointment for him and us given the way he's been performing this season."

The attrition level for Leinster scrumhalves is manifest in the injuries sustained by Easterby, Whitaker and now Willis.

One player who can look forward to plenty of action over the Christmas period is flanker Stephen Keogh, who has commandeered the number six jersey with a series of excellent performances in recent matches.

He returns "home" next Tuesday, but there will be little festive cheer being dispensed for 80 minutes if he lines out for Leinster against the team he left to join them, Munster.

The Limerick native is, however, looking forward to the trip to Thomond Park - though he is at pains to downplay its significance for him on a personal level.

"I grew up with a lot of the lads at Munster, but time moves on and I think they all respected my decision to move to Leinster," he says. "There will be good banter as the game approaches but it'll all be good-natured.

"I'm really enjoying life in Dublin with Leinster. I honestly feel as though we are going in the right direction. We're reasonably happy about our form in our last three outings: up in Ravenhill three weeks ago, against Agen in Lansdowne Road the other week and then in the away leg last weekend, where we showed a lot of grit.

"You have to win in France to have serious hopes of progressing in the tournament and we were all pleased even if we do know there are areas that we can improve on.

"We're all on the same road, but we haven't reached the goals we've set ourselves, so until that happens we'll keep on working hard."

The life of a professional rugby player has several drawbacks, one of which is an curtailed rest schedule over the Christmas period. Keogh smiles: "We're all working hard even though it's Christmas week. You could say Christmas has been cancelled, but that's just one of the sacrifices you make. It's the same for all the players."

It'll be a strange experience for Keogh to go in the Thomond Park gate, denied the support of a passionate crowd. He may have to consciously avoid making for the home dressing-room, a reflex action that would be forgiven in a player who wore the red of Munster with distinction.

"Any team that goes to Thomond Park will be underdogs," he admits. "It's incredibly tough to go down there and it will be a new experience for me to go down there as an opponent rather than a member of the home side. It's no secret that there's a great atmosphere in the ground. You only have to look at and listen to the noise at the Sale game there last year to get a flavour of it. The noise was incredible.

"I have found that the Leinster support this year has been incredible. Okay, Lansdowne Road is a bigger stadium, but it really makes it difficult for away teams when our supporters get behind you. I know we'll have a big following down in Limerick and that will give us all a real boost.

"I haven't dwelt on the game next week . . . Don't get me wrong; playing with Munster was an honour and there were obviously some great times, but life moves on. People move on. You can't concentrate on the past."

Serious bragging rights are at stake; it's a question of dishing it or being dissed.