A last minute try from Ronan O'Mahony saw Munster clinch a narrow 16-10 victory over a 13-man Scarlets side at Musgrave Park.
In a scrappy first half, where defences were on top, JJ Hanrahan and Aled Thomas traded penalties as the teams went into the interval level at 3-3.
John Barclay's try then gave the Welsh region a 10-3 lead before a pair of Hanrahan three-pointers set up a frantic finale. And after Rob Evans and Mike Poole had received yellow cards for the visitors, O'Mahony touched down for the winning score.
Following their respective Heineken Cup excursions, both sides decided to make numerous changes for this encounter and that lack of continuity was particularly evident in the first half.
There was a lack of creativity on show, but Thomas did open the Scarlets' account after 14 minutes through a penalty. Although Hanrahan levelled matters with a three-pointer of his own, that proved to be the final score of the half.
Proceedings livened up significantly after the interval. The second period was just a minute old when Kristian Phillips broke down the right touchline and off-loaded to Rob McCusker. Despite McCusker's surge being halted, the ball was fed to Thomas who spotted a gap and sent Barclay across the whitewash for a superb try.
Almost immediately Hanrahan reduced the deficit and added his third from the tee to take them to within one point of the visitors. Munster continued to lift the intensity as the match entered its latter stages but, with an opportunity to win the game, their fly-half missed the target from a penalty chance.
However, the Irish province were boosted late on by the sin-binnings of Evans and Poole and the Welsh side eventually succumbed when O'Mahony crossed the line.
Pens: Hanrahan 3
Con: A Thomas
Pen: A ThomasYellow Cards: Evans, Poole
Munster: 15 Denis Hurley, 14 Gerhard van den Heever, 13 Casey Laulala, 12 Ivan Dineen, 11 Andrew Conway, 10 JJ Hanrahan, 9 Cathal Sheridan, 8 Tommy O'Donnell, 7 CJ Stander, 6 Dave O'Callaghan, 5 Donnacha Ryan, 4 Billy Holland (c), 3 BJ Botha, 2 Duncan Casey, 1 Dave Kilcoyne
Replacements: 16 Damien Varley, 17 James Cronin, 18 John Ryan, 19 Ian Nagle, 20 Barry O'Mahony, 21 Duncan Williams, 22 Johnny Holland, 23 Ronan O'Mahony
Scarlets: 15 Gareth Owen, 14 Liam Williams, 13 Gareth Maule, 12 Adam Warren, 11 Kristian Phillips, 10 Aled Thomas, 9 Rhodri Williams, 8 Rob McCusker (c), 7 John Barclay, 6 Josh Turnbull, 5 Richard Kelly, 4 Jake Ball, 3 Jacobie Adriaanse, 2 Ken Ownes, 1 Rob Evans
Replacements: 16 Emyr Phillips, 17 Shaun Hopkins, 18 Rhodri Jones, 19 Johan Snyman, 20 Dan Thomas, 21 Gareth Davies, 22 Rhys Priestland, 23 Mike Poole
Referee: Nigel Owens (Wal)