Connacht skipper Andrew Farley is one of five players due to undergo fitness tests on Friday, ahead of Saturday's quarter final, second leg clash with Grenoble.
Meanwhile, Heineken Cup Pool 4 leaders Munster named a 25-man squad on Tuesday, for their trip to face NEC Harlequins at Twickenham. Centre Rob Henderson is in contention, having missed last weekend's 20-10 defeat of the Ospreys due to a slightly fractured cheekbone, and he is seeking confirmation from specialists on whether he is fit to play.
Ulster - who still have an outside chance of making the last eight - were buoyed yesterday by the inclusion of seven players in Eddie O'Sullivan's 35-strong RBS 6 Nations training squad.
Coach Mark McCall will name his starting line-up on Friday, for Sunday's Pool 6 meeting with Cardiff, with winger Andrew Maxwell expected to start for the injured Tyrone Howe.
Saturday, January 15:Heineken Cup, Pool 4:NEC Harlequins v Munster, Twickenham, 1.00pm
Results so far:Munster: Round 1: W15-9 NEC Harlequins (home), Round 2: W20-18 Ospreys (away), Round 3: L19-12 Castres (away), Round 4: W36-8 Castres (home), Round 5; W20-10 Ospreys (home)
Christian Cullen, Mossy Lawlor, Shaun Payne, Mike Mullins, Rob Henderson, Anthony Horgan, Paul Burke, Peter Stringer, Marcus Horan, Frankie Sheahan, John Hayes, Donncha O'Callaghan, Paul O'Connell, Alan Quinlan, Denis Leamy, Anthony Foley (Capt), Gordon McIlwham, Jerry Flannery, Trevor Hogan, Jim Williams, David Wallace, Mike Prendergast, Jason Holland, James Storey, Paul Devlin.
Referee: Joel Jutge (France)
Pool 2:Leinster v Benetton Treviso, Lansdowne Road, 5.15pm
Results so far:Leinster: Round 1: W25-9 Benetton Treviso (away), Round 2: W30-11 Bath (home), Round 3: W92-17 Bourgoin (home), Round 4: W26-23 Bourgoin (away), Round 5: W27-23 Bath (away)
(15) Girvan Dempsey (14) Shane Horgan (13) Brian O'Driscoll (12) Gordon D'Arcy(11) Denis Hickie (10) David Holwell (9) Guy Easterby (1) Reggie Corrigan (Capt)(2) Shane Byrne (3) Emmett Byrne (4) Leo Cullen (5) Malcolm O'Kelly
(16) Ricky Nebbett (17) David Blaney (18) Ciaran Potts (19) Aidan McCullen (20) Brian O'Meara (21) Felipe Contepomi (22) Kieran Lewis
Referee: Eric Darriere (France)
Challenge Cup: Quarter final, Second leg:Connacht (26) v Grenoble (21), The Sportsground, 2.00pm
Route to the Quarter final:Connacht: First round: L11-25 Narbonne (away), W40-21 Narbonne (home)Second round: W56-3 Montpellier (home), L14-19 Montpellier (away)Quarter final: W26-21 Grenoble (away)
Forwards: Ray Hogan, Peter Bracken, Adrian Clarke, Stephen Knoop, Bernard Jackman, John Fogarty, Andrew Farley (Capt), Pieter Myburgh, Christian Short, Michael Swift, Matt Lacey, John Muldoon, John O'Sullivan, Paul Neville Brendan O'Connor.
Backs: Tom Tierney, Chris Keane, Mike Walls, Eric Elwood, Paul Warwick, David Slemen, Ted Robinson, Conor McPhillips, Darren Yapp, Niall O'Brien, James Downey. Matt Mostyn.
Referee: Hugh Watkins (Wales)
Sunday, January 16:Heineken Cup, Pool 6:Cardiff Blues v Ulster, Arms Park, 3.00pm
Results so far:Ulster: Round 1: W21-16 Cardiff Blues (home), Round 2: L55-13 Gloucester (away), Round 3: L30-10 Stade Francais (away), Round 4: W18-10 Stade Francais (home), Round 5: W14-12 Gloucester (home)
To be confirmed
Referee: Christophe Berdos (France)