Munster lock Donncha O'Callaghan is poised to overtake Ronan O'Gara to become the province's most-capped player if he features this weekend.
The 34-year-old, who recently put pen to paper on a new two-year contract, is likely to surpass the former Ireland number ten on matches played.
More positive news is that back-row Tommy O'Donnell and full-back Felix Jones returned to the squad after being released by Ireland.
A statement added: "Donnacha Ryan made the step up to full training as he continues to regain full fitness following a knee injury with Ivan Dineen also back in full training after injuring his ankle playing for Munster A against Nottingham."
"Paddy Butler will return to training later in the week after injuring his neck while playing for Shannon in January.
"It's good news for Keith Earls as the Limerick man is on target with his rehab and will be looking to return in the next 4-6 weeks."