Conor Murray, another of the province's injury concerns, has also returned to training following the knee injury that he sustained in Ireland's RBS 6 Nations draw to France.
Speaking after the loss to Leinster, Tony McGahan said: "No one is ruled out (of the Ulster game) at this stage. We hope to have them all for selection from Tuesday to see how they train and get through. We would be hopeful.
"Paul O'Connell, Donnacha Ryan and Conor Murray have a fair chance of getting through at this stage.
"Denis Hurley trained most of the week. He had a bad 'cork' injury. We felt it prudent not to put him in a position to play this week.
Home advantage could prove crucial for McGahan's men this weekend. A notable statistic shows that the 60 Heineken Cup quarter-finals to date have ended with the home team winning 46 times and the away team going through to the semi-finals on 14 occasions - an average of less than one away win per season.
It means almost 77% of the quarter-finals have gone with home advantage with four-times champions Toulouse accounting for seven of those home wins, Munster six and Leicester Tigers five.
Indeed, the Munstermen are the only team to have won three away quarter-finals, at Stade Jean-Bouin against Stade Francais Paris (2002), at Welford Road against Leicester Tigers (2003) and at Gloucester in 2008.
MUNSTER Squad (v Ulster) - Backs (13): Johne Murphy, Ian Keatley, Tomas O'Leary, Felix Jones, Denis Hurley, Keith Earls, Lifeimi Mafi, Simon Zebo, Ronan O'Gara, Conor Murray, Danny Barnes, Duncan Williams, Scott Deasy.
Forwards (17): David Wallace, Donnacha O'Callaghan, Stephen Archer, Marcus Horan, Damien Varley, James Coughlan, Tommy O'Donnell, Peter O'Mahony, Paul O'Connell, Donnacha Ryan, BJ Botha, Mike Sherry, Wian du Preez, Mick O'Driscoll, Billy Holland, John Ryan, Denis Fogarty.