O'Driscoll remains a doubt

European Cup team news: A question mark continues to hang over Brian O'Driscoll's availability for tomorrow night's Heineken Cup meeting with Castres. The centre will undergo a fitness test ahead of the match with Felipe Contepomi ready to step in if needed.

After a mixed week on the injury front for the Leinster backroom staff, Shane Jennings is back in the starting line-up while Contepomi and Isa Nacewa have been named on the replacements bench at this stage.

But O'Driscoll's hamstring problem could yet rule him out while Shane Horgan is a definite non-starter after coming down with the bug which has swept through the squad recently. Simon Keogh, a try scorer from the bench at the RDS, starts in place of Horgan.

Ulster, still clinging onto faint hopes of qualification for the knockout stages, are also on the road tomorrow night and will look to build on last weekend's success against the Scarlets at Ravenhill.

Irish internationals Isaac Boss and Paddy Wallace return to the starting line-up for the trip to Parc y Scarlets. Boss comes in at scrumhalf for the injured Cillian Willis while Paul Steinmetz makes way for the fit-again Wallace. Willis was ruled out earlier in the week having fractured a cheekbone in training.

Speaking ahead of the trip to Wales, coach Matt Williams was thinking less of a place in the last eight and more of a first away win of the season.

"Winning away from home in Europe and the Magners League is something we have just got to address," he stated. "The field is exactly the same size, the same width and there is no reason for it.

"That we have never done it is not an excuse. It is completely irrelevant . . . it is not acceptable to me, it is not acceptable to anyone within the organisation. I told the boys that it is purely mental. They have got to front it up."

Michael Bradley has made two changes to the Connacht side to face Rugby Rovigo in the European Challenge Cup at the Sportsground on Friday.

Adrian Flavin starts at hooker, while David Gannon comes into the backrow for the injured Johnny O'Connor. The only other change to the 22 sees Mel Deane take his place on the bench.

Leinster(v Castres): G Dempsey; S Keogh, B O'Driscoll, L Fitzgerald, R Kearney; J Sexton, C Whitaker; S Wright, B Jackman, CJ van der Linde; D Toner, M O'Kelly; R Elsom, S JenningsJ Heaslip. Replacements: B Blaney; C Healy, T Hogan, S O'Brien, C Keane, F Contepomi / F McFadden, I Nacewa.

Ulster(v Scarlets): B Cunningham; A Trimble, D Cave, P Wallace, S Danielli; I Humphreys, I Boss; J Fitzpatrick, R Best, BJ Botha, E O'Donoghue, R Caldwell, S Ferris, D Pollock, R Diack Replacements: N Brady, T Court, M McCullough, K Dawson, P Marshall, P Steinmetz, C Schifcofske

Connacht(v Rovigo): F Carr; T Nathan, G Duffy (C), K Matthews, D Riordan; I Keatley, F Murphy; B Wilkinson, A Flavin, R Morris; A Browne, A Farley; D Gannon, R Ofisa, M McCarthy. Replacements: S Cronin, J Lyne, B McGovern, M Swift, K Campbell, T Donnelly, M Deane.