Star men Brian O'Driscoll, Sean O'Brien, Stephen Ferris, Rob Kearney and Rory Best are all ruled out for the hosts but lock O'Connell and prop Healy have returned to training after respective back and shoulder problems.
"Paul trained fully today and did everything in training - scrum, line-out and contact," assistant coach Mark Tainton said.
"We'll see what happens over the next 24 hours but we don't envisage any reaction to what he did today. It's looking good from his side.
"Cian did a full session today and there were no problems with his shoulder during a live scrummaging session. He showed full power."
O'Connell, who led the British & Irish Lions for the South African tour of 2009, seems the most likely candidate to assume the captaincy in O'Driscoll's absence - but Tainton suggested Jonny Sexton is also in the running.
Tainton added: "A fly-half's role is to lead the team anyway. Goalkicking and punting are just a part of his job. I wouldn't see it being a burden to take on the captaincy as well."
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