6 Dec, 10:47
Ireland will take on South Africa, Australia and a leading European Tier 2 nation at the Aviva Stadium during the GUINNESS Series in November 2014.
Thomas kicked the Welshmen ahead in the 68th minute before Andy Fenby pounced on a Felix Jones mistake to score his sixth try in this season's RaboDirect PRO12.
Thomas added an excellent conversion, but Munster answered back in injury-time with replacement JJ Hanrahan's penalty earning them a last-gasp losing bonus point.
It took a while for this encounter to ignite with a testing wind and French referee Laurent Cardona's whistle having the most influence.
Munster full-back Jones tested the Scarlets rearguard with a dangerous kick chase, and the first sniff of a try saw hooker Mike Sherry hauled down a couple of metres out.
The Scarlets, missing 15 players due to international call-ups, absorbed the early pressure and had the first shot at the posts - but Thomas' wind-affected effort swung away to the left of the target.
Into the second quarter, Keatley and Thomas swapped penalties with both sides guilty of unforced errors and static play.
The changes in personnel were an obvious factor and a long injury stoppage for the unfortunate Niall Ronan, late in the first half, also broke up the momentum.
Ronan suffered a blow to the head as Jake Ball hurtled into a ruck near halfway, which may result in the young Scarlets lock being cited.
Munster hunted for a late try and Ronan's replacement, South African recruit CJ Stander, was held up on a close range drive in injury-time.
With the rain now teeming down into Munster faces, the Scarlets resumed in better fettle and Ball's charge down almost led to the onrushing Jonathan Edwards scoring.
Thomas slid a penalty wide, failing to punish Munster for a scrum infringement. Spilled passes were a regular occurrence as the conditions worsened.
A drop goal shot from Thomas went the wrong side of the left hand post, and the Munster forwards responded with a strong spell of carrying and direct running.
Jones lifted the home crowd with two surges from deep, the second of which led to Keatley hacking through and the Scarlets had to scramble back close to their try-line.
The Welsh region edged ahead with 12 minutes remaining, Thomas planting a penalty over with the aid of the left upright amid a strong period of scrummaging.
Led by man-of-the-match Emyr Phillips, Simon Easterby's men held the upper hand in the scrum and continued to win decisions from referee Cardona.
Munster handed them a very soft try shortly afterwards. The Scarlets launched a kick chase after Luke O'Dea coughed up possession in midfield, the retreating Jones had two bites at the loose ball but it squirted free over the whitewash for Fenby to flop on it.
Thomas' successful conversion put the seal on the Scarlets' first victory over Munster in 16 meetings, stretching back to 2007. The number 10 had two further penalty chances but he missed both, the first striking the woodwork.
For their part, Munster used possession well to carve out a late penalty, allowing Hanrahan to split the posts with the final kick of the game.
|Munster Rugby Score Card|
|Scarlets Score Card|