Toulon snatched a late victory from the grasp of 14-man Scarlets in the European Challenge Cup.
Gervais Cordin's try had put Toulon ahead before Johnny McNicholl replied for Scarlets, who had Tevita Ratuva sent-off.
Dan Jones' penalty and drop goal gave the visitors a 16-10 lead but they were to be denied deep in a dramatic finale.
Liam Messam's try and Anthony Belleau conversion deep in stoppage time snatched the win.
Scarlets had put up a brave fight and showed determination and character at the partisan Stade Mayol.
Steff Hughes crossed the try line after four minutes but unfortunately for Scarlets the ball had been knocked on.
Toulon went ahead when Louis Carbonel's cross field kick found Gervais Cordin to trot in for the first try, which was converted by Anthony Belleau.
But Scarlets responded when McNicholl intercepted and an easy run in for the new Wales call-up saw him touch down for his side's first try.
Ryan Lamb added the conversion to bring the sides level although Belleau restored Toulon's lead.
But the Scarlets' hopes suffered a setback at the end of the first half with lock Ratuva red carded for using his shoulder illegally on Mamuka Gorgodze.
Despite being down to 14 men, Scarlets struck first in the second half as Lamb's penalty brought them level.
Belleau had an opportunity to edge Toulon once more but his kick struck the upright before a penalty and a drop goal from replacement Jones.
Scarlets were arguably the better of the two sides in the second half despite being a man down but they were to be denied at the death.
Toulon had a try ruled out by the TMO before ex-New Zealand forward Liam Messom scored his side's second try before Belleau's conversion secured victory at the death for the former European champions.
Scarlets had opened their Challenge Cup campaign with a 20-16 win against London Irish, while Toulon defeated Bayonne 20-13.
Toulon: Heem; Cordin, Te'o, Belleau, Ikpefan; Carbonel, Serin; Gros, Etrillard (capt), Setiano, Gorgodze, Rebbadj, Horau, Ollivon, Messam.
Replacements: Soury Taofifenua, Gigashvilli, Vernet, Parrise, Heritau, Schreuder, Dachary.
Scarlets: McNicholl; Baldwin, Hughes (capt), Fonotia, S Evans; Lamb, Blacker; R Evans, Elias, Lee, Ratuva, J Kruger, Shingler, Macleod, B Thomson.
Replacements: M Jones, P Price, Sebastian, Helps, Cassiem, Hardy, D Jones, M Williams.
Referee: Tom Foley (England)
Assistant referees: Jack Makepeace (England), Phil Watters (England)
TMO: Stuart Terheege (England).