Munster were knocked off the top of the RaboDirect PRO12 table as they were upset 29-19 by Benetton Treviso in Italy.
Ludovico Nitoglia had two tries while Mat Berquist kept the points flowing from his boot as Munster missed out on the chance to become the first side ever to begin a league season with maximum points from their opening three games.
Keith Earls and Stephen Archer both crossed Munster, but ill discipline cost them as Berquist amassed 19 points, scoring five penalties, while three different Munster players endured spells in the sin bin.
Things began well for Munster as they bossed the opening stages with Earls opening the scoring with a seventh-minute try.
But Ian Keatley, having already missed a penalty, was off target with the conversion, and two Berquist penalties soon saw the momentum swing the other way.
Munster regained the lead with a penalty try when Treviso's scrum collapsed after a gutsy call from captain Peter O'Mahony, Keatley finding his aim this time to make it 12-6.
Another Berquist penalty cut the deficit before half-time but when Archer crossed early in the second half, Keatley's conversion pushed Munster's advantage into double figures and all looked well for the Irish.
That feeling lasted only a couple of minutes before Nitoglia notched his first try, and Berquist's penalty on the hour mark had the teams tied once more.
Nitoglia then dove over from close range for his second score and Berquist sealed it with Munster again down in numbers as Cathal Sheridan took his turn in the sin bin.