Ludovico Nitoglia crossed twice for Benetton Treviso and Mat Berquist kicked superbly as the Italians upset previous table toppers Munster in a 29-19 win in the RaboDirect PRO12.
The Irish region came to the Stadio di Monigo bidding to become the first side ever to begin a league season with three maximum point victories but ill-discpline cost them dear.
Treviso have twice before beaten Munster and despite conceding three tries from Keith Earls, a penalty score and Stephen Archer they had enough to emerge comfortable victors in the end.
Nitoglia’s two scores in the second half turned the game on its head while Kiwi Berquist added 19 points from the kicking tee.
And in a bad tempered affair Rob Penney’s side ended up with four different players sent to the sin bin, three of them in the second half.
Ian Keatley, restored to the side ahead of JJ Hanrahan, missed a penalty in the fifth minute on a chastening night for th fly-half but it was the Irish region who were dominant in the opening stages.
And it was the impressive Earls, lining up at right wing, who notched the first try of the match as early as the seventh minute, scorching clear down the right after being fed by Simon Zebo.
Keatley was again off target with the conversion and the Italian outfit began to grow into the encounter as it wore on.
And Kiwi Berquist was looking in fine form from the kicking tee, the former Leinster man slotting over two penalties in the 13th and 17th minute to put the Italians 6-5 in front.
In between those two incidents Niall Ronan was also sent to the sin bin for an apparent punch but down to 14 men the Irish region managed to hold out.
And restored to their full quota Munster were soon back on the front foot and took the lead again as the forward pack earned a penalty try.
They were dominating in the scrum and twice earned penalties, the second eminently kickable on the try-line but skipper Peter O’Mahony turned it down and called for another scrum.
And it was third time lucky as the referee was left with no option but to award a penalty score as Treviso again collapsed under the pressure of the Munster pack.
Keatley’s conversion made it 12-6 and vindicated O’Mahony’s gutsy call to go for all seven points instead of settling for three.
But a third Berquist penalty before the half-time whistle meant that Treviso were still very much within touching distance, only trailing 12-9 at the break.
It was Munster who had the first score after the interval and then looked the more likely winners, Archer going over in the 47th minute and Keatley converting to make it 19-9.
But after that the second half belonged to the Italians, in the 49th minute Nitoglia was over for his first try, cantering over untouched after a huge overlap down the right.
Berquist’s conversion closed the gap to 19-16 and his subsequent penalty on the hour mark, his fourth of the night, levelled the scores.
And with confidence now flowing the Italians were soon in front, Nitoglia diving over from close range for his second down the right after the Treviso pack made inroads up the middle, Berquist again on target with the extras.
Munster’s discipline was fading badly at this point Duncan Williams sinbinned on the hour mark and Cathal Sheridan following him just four minutes later.
Berquist punished that indiscipline with another penalty to make it 29-19 and the match was effectively over.
And an impossible task was made even harder late on when Archer was the fourth Munster man sent to the sin bin and Treviso held on for a famous victory.