Ronan O’Mahony and Duncan Williams were the try-scoring heroes as Munster picked up their first win of their pre-season and handed new head coach Anthony Foley his first victory.
Played in front of a 5,000 sell-out at the Waterford RSC, Munster showed much improved form from their previous outing against Gloucester and Foley will be happy with impressive debuts from centre Andrew Smith and No 8 Robin Copeland, while Darren Sweetnam and CJ Stander also shone for the home side.
Munster led 7-5 at the end of a disjointed first-half, but ratcheted up the pressure on London Irish after the restart and powered to a deserved victory.
However a knee injury for centre Cian Bohane was the major sour note from the evening. Bohane had to be stretchered from the field in the final minutes after he sustained the injury, a huge setback for him after two impressive starts in pre-season.
Munster got off to a good start though and after dominating territorially in the opening minutes, young fly-half Johnny Holland declined a kickable penalty following a London Irish infringement in a Munster maul. And after a super take from Billy Holland started the move, a superbly executed choke tackle a couple of phases later halted the experienced second-row's run.
Three minutes later Munster's No 10 received orders to kick to the corner again when excellent breaks by Sweetnam and Stander forced London Irish into conceding a penalty at a ruck. But after some solid pressure from Munster they coughed up possession in the scoring zone.
Both Donncha O'Callaghan and his opposite number Jebb Sinclair were sin binned in the 29th minute following an off-the-ball altercation, and with both sides a man down Munster hit the front.
Stander was the chief architect of the move as his powerful, driving run caused the London Irish defence to narrow, and Cathal Sheridan spotted the three-versus-one overlap and sent O'Mahony over for a simple finish.
There was nothing easy about Johnny Holland's conversion, which gave Munster a 7-0 lead in the 36th minute, but the home side's joy was short lived when a nice move down the right wing produced a try, as Tom Fowlie sent Alex Lewington over in the corner.
Munster held a 7-5 lead at half-time, but despite a high error rate, Foley's side continued to dominate their visitors.
Matt Parr was yellow carded for London Irish for a scrum infringement in the 43rd minute, and during that numerical advantage Billy Holland almost got over in the corner, and only a late Will Harries clearance denied the big lock.
But Munster held on to the territorial dominance and after O'Callaghan, Holland and Sean Dougall came within inches of breaking the try line, Duncan Williams bagged Munster's second try when he wriggled over from close range in the 59th minute.
Once again Johnny Holland made no mistake with the conversion to stretch Munster's lead to 14-5, and when he slotted his first penalty attempt 12 minutes from time there was no way back for London Irish.
Munster: J Murphy (R Scannell 68); R O'Mahony, A Smith (D Johnson 68), C Bohane (J Murphy 75), D Sweetnam (I Dineen 60); J Holland, C Sheridan (D Williams 40); J Ryan (A Cotter 75), K O'Byrne (G Slattery 62) (D Casey 76), S Archer (BJ Botha 51); D O'Callaghan (J Madigan 75), B Holland; CJ Stander (B O'Mahony 68), S Dougall (S McCarthy 68), R Copeland (S Buckley 62).
