As an Irishman, Conor O'Shea was in no doubt over the scale of the achievement by his Harlequins side after they became only the second team in 16 years to win a European match in Limerick. But Quins' director of rugby did add a cautionary note by stating that earning a place in the Amlin Challenge Cup final, against another mighty opponent in Stade Français in Cardiff on 20 May, meant that they had done "nothing" yet.
In 41 previous European games at Thomond Park, only Leicester, in a Heineken Cup pool game in 2007, had overcome the hosts. But from before the game even kicked off, O'Shea felt they were on to something.
"We won the toss and [our captain] Chris Robshaw came up to me and said that he wanted to play into the wind because he wanted us to play our game," said O'Shea. "The minute he said that I knew we would be fine in terms of bringing our game to Thomond. I'm delighted for the players because of the work that they have put in. We might not have the squad size that a lot of teams have but we have a hell of a lot of heart. I'm incredibly proud, as you can imagine for various different reasons. But the horrible thing is that we have done nothing. We have won a semi-final.
"My dad has a saying that a good semi-final never makes a good final, so we're going to have to make sure that that doesn't happen. But the guys will have today's win in their locker forever and a day."
The victory came despite having to play the last 10 minutes without Nick Easter, who was sent off for a second yellow card offence. Quins were clinging on somewhat at the end but the visitors dominated possession and territory in a frenetic opening salvo, Nick Evans sending a delicious wide ball for Gonzalo Camacho to slalom past Paul Warwick and Doug Howlett. He was hauled down close to the try-line but Quins swiftly moved the ball wide to the right, where lock George Robson dived in past James Coughlan.
Evans topped the ninth-minute try with a well-struck conversion and the Londoners' early barrage continued with the forwards regularly crossing the gain line. Quins maintained their attacking poise and at a ruck, Munster's overworked defence was caught out by Danny Care's feint and stretch for the line. The England scrum-half had enough downward pressure with his fingertips to satisfy television match official Giulio de Santis, with Care adding the conversion himself.
Ronan O'Gara turned down a kickable penalty as Munster went in search of their first points late on. Their endeavour was rewarded when Lifeimi Mafi and Warwick straightened for Felix Jones to come in on an angle and glide over from close range. O'Gara landed the conversion to give Munster a further boost. Donncha O'Callaghan and Easter earned time in the sin-bin for scuffling off the ball, before Rory Clegg slotted a right-sided penalty for Quins in the 50th minute.
Mike Brown was alert to cover a chip-and-chase from Doug Howlett, who got over for a deserved try in the 78th minute. A ruck offence had seen Easter walk eight minutes earlier, and the former All Black struck from close range to give Munster late hope.
But O'Gara's conversion attempt from wide out on the right was off-target and Harlequins' heroic defence, led by Robshaw, was rewarded at the final whistle.
"The way that we played didn't give us any opportunity whatsoever to get a result," admitted Munster head coach Tony McGahan.
Munster: Tries Jones, Howlett; Conversion O'Gara.
Harlequins: Tries Robson, Care; Conversions Evans, Care; Penalties Clegg (2).
Munster: F Jones; D Howlett, L Mafi (J Murphy, 65), P Warwick (S Tuitupou, 40), K Earls; R O'Gara (capt), C Murray (P Stringer, 57); W du Preez (M Horan, 57), D Varley (Sherry, 74), T Buckley (J Hayes, 40), D O'Callaghan (D Ryan, 68), M O'Driscoll (P O'Connell, 40), D Leamy, D Wallace, J Coughlan.
Harlequins: M Brown; G Camacho, G Lowe, J Turner-Hall, U Monye; N Evans (R Clegg, 40), D Care; J Marler (C Jones, 66), J Gray, J Johnston; O Kohn (T Vallejos, 73), G Robson, M Fa'asavalu, C Robshaw, N Easter. Referee: Romain Poite (France).