Glasgow led 6-0 at half-time thanks to two penalties from Finn Russell
The Warriors were down to 13 men for seven minutes in the second half but managed to limit the damage, holding on for a 9-6 win
The match was the Scottish sides’ 100th match in the Champions Cup
Glasgow Warriors marked their 100th game in the European Cup by doing the double over Guinness PRO12 rivals Scarlets to stay in the hunt for a quarter-final place in the European Champions Cup.
In appalling conditions at Parc y Scarlets, Gregor Townsend’s team celebrated their century with four points and also made it back-to-back victories in the middle of the pool stages for the first time in 15 seasons as they triumphed 9-6.
Gusting winds and torrential rainfall made for sodden conditions, fiendishly difficult for handling and hardly conducive to producing five-try victories.
Warriors raced into a 9-0 lead through three penalties from Finn Russell but they were forced to dig deep in the second half when they were reduced to 13 men for seven minutes after the former Scarlets player Sean Lamont and back-row man Chris Fusaro were both sent to the sin-bin
Aled Thomas clawed the hosts back into the game with a pair of penalties, however missed a 45-metre kick at goal late on which would have snatched a draw for the Welsh region.
MAN OF THE MATCH
Glasgow: Alex Dunbar
Scarlets: 15 Mike Collins, 14 Steff Evans, 13 Gareth Owen, 12 Hadleigh Parkes, 11 DTH van der Merwe, 10 Aled Thomas, 9 Gareth Davies, 8 Morgan Allen, 7 Jack Condy, 6 Lewis Rawlins, 5 Maselino Paulino, 4 Jake Ball, 3 Samson Lee, 2 Emyr Phillips (c), 1 Rob Evans.
Replacements: 16 Ken Owens, 17 Wyn Jones, 18 Rhodri Jones, 19 George Earle, 20 Tom Price, 21 Aled Davies, 22 Steven Shingler, 23 Harry Robinson.
Glasgow Warriors: 15 Tommy Seymour, 14 Taqele Naiyaravoro, 13 Mark Bennett, 12 Alex Dunbar, 11 Sean Lamont, 10 Finn Russell, 9 Mike Blair, 8 Josh Strauss, 7 Simone Favaro, 6. Robert Harley, 5 Jonny Gray (c), 4 Leone Nakarawa, 3 Sila Puafisi, 2 Fraser Brown, 1 Alex Allan..
Replacements: 16 Shalva Mamukashvili, 17 Gordon Reid, 18 Zander Fagerson, 19 Tim Swinson, 20 Ryan Wilson, 21 Grayson Hart, 22 Duncan Weir, 23 Lee Jones.
Date: Saturday, December 19
Venue: Parc y Scarlets
Kick-off: 19:45 GMT
Referee: Pascal Gauzère (France)
Assistant Referees: Maxime Chalon (France), Jean-Luc Rebollal (France)
TMO: Bruno Bessot (France)