Scarlets held on for a draw in the Heineken Cup against Racing Metro who were 20-10 down at the break.
The French visitors led through Wenceslas Lauret's try and Jonathan Sexton's kicking.
Rhys Priestland's boot and tries by Scott Williams and Rhodri Williams put the hosts ahead.
Amid the Priestland-Sexton kicking duel, Racing's Masi Matadigo went over and Lauret was denied at the death by Sexton's knock-on in the build-up.
The Llanelli-based region's backs were again full of invention and craft, but the visitors' pack had the edge of their opponents.
Simon Easterby's side went into the clash boosted by their stunning opening round win at Harlequins while Racing Metro saw off beaten 2013 beaten finalists Clermont Auvergne 13-9 in Paris.
At Harlequins, the the west Wales region established an early lead, but against this week's opponents, the hosts had to battle back.
Racing took advantage of a disintegrating Scarlets scrum for flanker Lauret to gather and touched down, Ireland international Sexton adding the conversion.
The British and Irish Lions fly-half added a penalty before Priestland put the home side on the scoreboard with his first shot at goal.
Priestland helped create Scarlets' opening try as his innocuous-looking clearance bounced high, allowing Nic Reynolds to reach it.
The wing tapped the ball into Jonathan Davies' arms and he sent Scott Williams away for the Wales challenger's second spectacular European try in six days.
Priestland added the conversion and after Sexton missed a penalty, made amends by punishing Racing skipper Dimitri Szarzewski's yellow-card indiscretion at a ruck.
Worse was to follow for the visitors, who saw replacement centre Fabrice Estebanez sin-binned following an off-the-ball clash with Scott Williams.
That left the French side with 13 men for six minutes and when given the option to kick for goal or bid for a try from a close-range line-out, Scarlets chose the latter.
The gamble paid off when scrum-half Rhodri Williams broke through the depleted defence to score.
Priestland converted to establish a 20-10 half-time lead for the hosts.
The Wales fly-half added another penalty early in the second period, but after being restored to a full complement, Racing launched their own fightback.
Sexton's penalty was followed by number eight Matadigo powering over from a dominant scrum.
The Ireland pivot added the extras before levelling with a penalty.
The fly-halves' kicking exchange continued until interrupted by the latter's uncharacteristic 73rd minute miss.
And there was dismay among the French side's ranks after Lauret's injury-time chase and touchdown was ruled out because Sexton had knocked the ball on as he stripped Josh Turnbull of possession.
Scarlets: L. Williams, Reynolds, J. Davies, S. Williams, J. Williams, Priestland, R. Williams, John, E. Phillips, Adriaanse, Ball, Earle, A. Shingler, Barclay, Turnbull.
Replacements: Evans for John (71), Snyman for Ball (65).
Not Used: Myhill, R. Jones, Price, G. Davies, S. Shingler, Maule.
Racing Metro 92: Lapeyre, Plante, Chavancy, Dumoulin, Imhoff, Sexton, Magnaval, Tonga'uiha, Szarzewski, Ducalcon, Kruger, van der Merwe, Lydiate, Lauret, Matadigo.
Replacements: Estebanez for Dumoulin (22), Snyman for Magnaval (57), Ben Arous for Tonga'uiha (61), Brugnaut for Ducalcon (67), Metz for van der Merwe (62), Lacombe for Matadigo (42).
Not Used: Gerondeau, Dambielle.
Sin Bin: Szarzewski (34), Estebanez (38).
Referee: Neil Paterson (Scotland).