The Scarlets fell agonisingly short of a first result against the Stormers, after pushing the South African outfit all the way in a high-scoring 52-40 defeat in Cape Town.
Wales centre Joe Roberts crossed for a hat-trick as the Scarlets came within touching distance of a draw at DHL Stadium. Even a victory seemed possible, with the scores locked at 40-40 heading into the final 10 minutes.
In the end, a couple of late scores robbed the west Walians of a losing bonus point - although their six tries ensured they weren't pointless after a remarkable effort.
Scarlets Missing Key Wales Call-Ups
The Scarlets had travelled to South Africa without five of their seven Wales call-ups; Blair Murray, Ellis Eddie James, Sam Costelow and Ryan Elias all left at home.
The early exchanges had been fairly even, with some of the hosts' Springbok stars strangely error-strewn.
However, things turned after hooker John McKee was sent to the sin-bin for a breakdown infringement.
Stormers Forge Ahead
The home side forged ahead with two quickfire tries. First, Zachary Porthen powered over from a smartly-worked driving maul. Then, Hasseim Pead was put over after a bit of magic by South Africa fly-half Sacha Feinberg-Mngomezulu.
The Scarlets hit back while down to 14 men, with quick hands from Joe Hawkins and Ioan Jones putting Joe Roberts over out wide.
Loosehead Nthuthuko Mchunu then restored the Stormers' lead, racing through a gap from the back of a maul. Back came the Scarlets, with Carwyn Leggatt-Jones lofting a floated ball over the top for Ioan Jones to finish superbly out wide.
After Seabelo Senatla dotted down for the Stormers' bonus-point try, Jones looked to have scored a second - only for a lovely move to be pulled back for a forward pass by Leggatt-Jones.
Rather than ending the half one score down, they would find themselves with a 19-point deficit - after Deon Fourie powered over after the clock had gone red.
Second-Half Fightback
However, a rapid start to the second-half brought Nigel Davies' side back into the mix.
The Scarlets continued to find joy with ball in hand, with Ioan Nicholas cutting through to set up the in-form Macs Page to score. In the week where he wasn't included in Wales' autumn squad, it was the perfect response by the 21-year-old.
Some pressure in defence brought the Scarlets their bonus point score minutes later, with Roberts picking off a pass in midfield to race away for his second.
Their strong start to the second-half saw Page nearly draw the sides level, getting outside Feinberg-Mngomezulu to nearly score. Unfortunately, the wing hit his head on the turf as he attempted to score - resulting in him leaving the pitch with the assistance of medics in concerning scenes.
The Stormers pushed further ahead, with Oliver Reid rumbling over to open up a two-score gap again.
However, the Scarlets wouldn't go away - with a delightful looping pass by replacement prop Sam O'Connor putting captain Josh Macleod over out wide. Then, with 15 minutes to go, Roberts went over for his hat-trick try after the Stormers failed to bring him down.
Some brilliant goal-line defence by the Scarlets denied the home side a go-ahead score nine minutes from time. However, they were helpless to stop Yaqeen Ahmed cutting through moments later, for what proved to be the winning score.
At the death, Ahmed capitalised on a Roberts knock-on to deny the Scarlets a second bonus point.
