A dominant final quarter saw Munster run out 42-7 winners as BKT United Rugby Championship returned to Parc y Scarlets.
The home side were right in the contest, trailing 14-7 on the hour mark, but the defending champions sensed blood late on to touch down for four converted tries in the space of 14 minutes.
Wales centre Joe Roberts scored a brilliant individual try as the Scarlets threatened a comeback, but Munster, with No. 8 Gavin Coombes a force of nature, showed their quality to emerge comfortable winners.
Before the game, Parc y Scarlets paid tribute to the great Barry John, who played 87 games for the club across four seasons.
Scarlets had early opportunities through short-range line-outs, but failed to make the most of the chances and instead it was Munster who delivered a lesson in being clinical with the opening score on 10 minutes.
It came via a short-range penalty move that saw player of the match Coombes cross, a score converted by fly-half Joey Carbery.
It needed some heroic defence, led by a big hit from Archie Hughes, to keep Munster at bay, but wave after wave of Munster forward assaults eventually saw Coombes driven over for his second on 24 minutes.
Trailing 14-0, Scarlets desperately needed something to lift the crowd.
A brilliant counter-attacking break by Johnny McNicholl did just that, but the Scarlets failed to keep the attack going, or come away with anything from another period of pressure on the Munster line.
It needed a try-saving tackle by Ioan Nicholas to haul down Springbok giant RG Snyman after an interception late in the half and Scarlets were able to get into the changing rooms without any further damage.
Nine minutes into the second half, the home crowd were on their feet thanks to Roberts’ stunning effort.
Hitting a great angle from a pass by co-centre Eddie James, the Six Nations squad member burst clear from 40 metres out, rode some last-ditch scrambling defence, but picked himself up and dived over. Replacement Charlie Titcombe converted.
The 7,000-plus crowd sensed Scarlets were clawing their way back into the contest, but the momentum was halted with a try by replacement Jack O’Sullivan and after that it was all Munster.
Lock Tom Ahern took an inside pass for the bonus-point score, then wing Sean O’Brien and another replacement Shay McCarthy rubbed further salt into the wounds.
Eighteen-year-old hooker Harry Thomas came on to make his senior debut in the final exchanges, a second debutant of the night after South African back-rower Jarrod Taylor had showed up well in the opening half before being forced off with injury at the break.
Scarlets – try: J. Roberts con: C. Titcombe
Munster – tries: G Coombes (2), J. O’Sullivan, T Ahern, S. O’Brien, S. McCarthy. Cons: J Carbery (6).
Scarlets: Johnny McNicholl; Tomi Lewis, Joe Roberts (repl Steff Evans 66), Eddie James, Ioan Nicholas; Dan Jones (repl Charlie Titcombe 49), Archie Hughes (repl Efan Jones 49); Kemsley Mathias (repl Wyn Jones 49), Eduan Swart, Harri O’Connor (repl Sam Wainwright 40), Alex Craig, Sam Lousi (capt; repl Jac Price 51), Jarrod Taylor (repl Teddy Leatherbarrow 40), Dan Davis, Vaea Fifita (repl Harry Thomas 66).