Munster are monitoring the fitness of several players ahead of their Champions Cup fixture against Stade Français in Paris on Sunday.
After helping Munster beat Treviso in Round One, Mike Sherry, Duncan Casey, Dave O'Callaghan and Conor Murray sat out Tuesday's session.
Stephen Fitzgerald and Tyler Bleyendaal also missed training.
"Following on from Saturday night's game against Treviso, Mike Sherry (knee) and Duncan Casey (pec) continue to be assessed by the medical team with both hookers waiting on scan results. In managing training workloads Conor Murray and Dave O'Callaghan both stood out of today's session, while Tyler Bleyendaal continues to manage a quad strain and remains unavailable," read an injury update on Munster's website.
"Peter McCabe (pec), Tommy O'Donnell (hip) and Stephen Archer (neck) all continue with their rehabilitation programmes while Peter O'Mahony (knee) will undergo surgery at the end of this week."