Munster were forced to overturn a half-time deficit as they beat a below-strength Treviso side 18-13 in Cork on Saturday.
Skipper CJ Stander scored two second-half tries as the hosts took control of the game having trailed 7-6 at the interval.
The Italian outfit finished last season in 11th position but they defied that performance with their display against the Irish province in the first period.
Dean Budd's try and Jayden Hayward's conversion was enough to give them the lead at the interval despite Ian Keatley's two penalties. But the hosts increased the intensity after the break and a pair of Stander touchdowns gave them the victory.
Hayward kicked two three-pointers late on which secured Treviso the losing bonus-point, but it was Munster who took the win.
Anthony Foley's men enjoyed an excellent season in last year's Pro12 up until the point they faced Glasgow Warriors in the final.
Perhaps looking to erase that disappointment from their minds, they started this campaign on the front foot with Rory Scannell impressing early on. The reward for their positivity with ball in hand was a penalty, which Keatley duly converted.
However, unfancied Treviso looked to defy the pundits and stamp their authority on proceedings by challenging the hosts' defensive line. Treviso caused the home side's rearguard a number of problems and Budd's try, following a succession of phases inside the opposition 22, was just reward for their ability to get over the gain-line and retain possession.
Hayward's conversion extended that advantage to four points but Keatley's second three-pointer reduced it to 7-6 at the break.
Even though the Irish province was short of their better players due to the upcoming World Cup, it was still a surprise to see a team containing the likes of CJ Stander behind to the Italian minnows.
But the number eight took it upon himself to improve their fortunes as he scored two second half tries.
Firstly, the South African touched down from close range before he latched onto Shane Monahan's break and pass to cross the whitewash.
All of a sudden, it looked a long way back for the visitors and it got worse when the pressure exerted by Foley's men resulted in a yellow card for Ludovico Nitoglia.
To the Italian outfit's credit, they managed to kick a penalty from the boot of Hayward while they were down to 14 men, and then added another with the final action of the encounter to earn a losing bonus-point.
Tries: Stander 2
Pens: Hayward 2
Yellow Card: Nitoglia
Munster: 15 Felix Jones, 14 Andrew Conway, 13 David Johnston, 12 Rory Scannell, 11 Shane Monahan, 10 Ian Keatley, 9 Duncan Williams, 8 CJ Stander (c), 7 Jack O'Donoghue, 6 Dave O'Callaghan, 5 Dave Foley, 4 John Madigan, 3 BJ Botha, 2 Mike Sherry, 1 James Cronin
Replacements: Niall Scannell, John Ryan, Stephen Archer, Robin Copeland, Shane Buckley, Cathal Sheridan, Tyler Bleyendaal, Cian Bohane.
Treviso: 15 Jayden Hayward, 14 Ludovico Nitoglia, 13 Tommaso Iannone, 12 Henry Bacchin, 11 Andrea Pratichetti, 10 Sam Christie, 9 Chris Smylie, 8 Braam Steyn 7 Dean Budd, 6 Robert Barbieri, 5 Tom Palmer, 4 Duncan Naude, 3 Rupert Harden, 2 Roberto Santamaria, 1 Alberto De Marchi (c),
Replacements: 16 Luke Bigi, 17 Zanusso Matthew, 18 Simone Ferrari, 19 Phillip Gerosa, 20 Jean-Francois Montauriol, 21 Marco Barbini, 22 Alberto Lucchese, 23 Simone Ragusi
Referee: Lloyd Linton (Scotland)
Assistant Referees: Stuart Gaffikin (Ireland). John Carvill (Ireland)
TMO: Alan Rogan (Ireland)