Munster 'A' completed the group stages with an 100pc record, following this victory at Bandon.
Head coach Peter Malone made six changes to the team that recorded a bonus point win in Doncaster last weekend, in a rescheduled clash.
Doncaster went in front, courtesy of a penalty from Dougie Flockhart, but the hosts responded in kind through out-half Te Aihe Toma, who had a successful night in front of goal.
Flockhart put Doncaster back in front before Munster blitzed their visitors with tries from Stephen Fitzgerald and Cian Bohane.
Although Flockhart closed the gap with his third penalty, Malone's men were resolute in seeing the game out, despite a late try from Doncaster replacement Sam Edgerley.
There was still time for another Munster try before the full time whistle, as John Poland powered his way over, to ensure those in attendance left the West Cork town satisfied with what they witnessed.
Munster now await what should be a home quarter-final.
This performance and result showed plenty of reasons why Munster can challenge for honours in this competition.
Munster A - D Johnston; C Nash, A McHenry, C Bohane , S Fitzgerald; TA Toma, J Poland; B Scott, K O'Byrne, S Archer; J Madigan, D O'Shea; D O'Callaghan, C Oliver, G Coombes.