A last second penalty from Steven Shingler helped the Scarlets beat Munster 25-22 on Friday, their fifth straight victory of the PRO12 campaign.
The first half saw only one try, which came through Munster full-back Andrew Conway.
Shingler and Ian Keatley each kicked two penalties, giving Anthony Foley's side a 13-6 lead at half time.
After the break, Scarlets scored two tries through World Cup star DTH Van Der Merwe and Tom Williams.
Two penalties and a drop goal from Keatley, with his opposite number Shingler kicking nine points of his own, saw Scarlets take the win in dramatic fashion.
The first points came on five minutes through Keatley. Despite holding much of the possession, the Scarlets failed to capitalise, losing four of their own line-outs and giving away several scrum penalties.
The game's first try came through Conway. A foot race between the two full-backs after a kick through saw the Munster man reach the ball just before his opposite number Aled Thomas.
Although it appeared that both failed to make significant contact with the ball, the TMO ruled that Conway had grounded the ball with his forearm.
Three penalties then followed, two for Shingler and one for Keatley. It was the away side with a seven-point lead going into the second half.
After the interval, the Scarlets scored their first try of the game through star winger Van Der Merwe. It was the Canadian's third try in two games since signing from Glasgow Warriors.
Munster then replied with another penalty from Keatley, before Scarlets scored their second try through replacement Williams, who grounded the ball after a kick through from Regan King. Shortly after scoring, Williams was given a yellow card for a high tackle.
Munster failed to take advantage of the extra man, with Keatley's drop goal on 60 minutes cancelled out by another Shingler penalty.
After a string of misses, a late Keatley penalty looked to have won the game for Munster. But Shingler slotted two penalties of his own, with the second coming long after the 80 minute mark.
This win ensured the home side maintained their unbeaten start to the season with five wins out if five.
Tries: Van der Merwe, T Williams
Pens: Shingler 5
Yellow Card: T Williams
Pens: Keatley 4
Drop Goal: Keatley
Scarlets: 15 Aled Thomas, 14 Hadleigh Parkes, 13 Regan King, 12 Gareth Owen, 11 DTH van der Merwe, 10 Steven Shingler, 9 Rhodri Williams, 8 John Barclay (c), 7 James Davies, 6 Lewis Rawlins, 5 Tom Price, 4 Jake Ball, 3 Samson Lee, 2 Ken Owens, 1 Rob Evans
Replacements: 16 Emyr Phillips, 17 Phil John, 18 Peter Edwards, 19 George Earle, 20 Jack Condy, 21 Gareth Davies, 22 Dan Jones, 23 Tom Williams
Munster: 15 Andrew Conway, 14 Stephen Fitzgerald, 13 David Johnston, 12 Denis Hurley, 11 Gerhard van den Heever, 10 Tyler Bleyendaal, 9 Cathal Sheridan, 8 CJ Stander (c), 7 Jordan Coghlan, 6 Dave O'Callaghan, 5 Mark Chisholm, 4 Robin Copeland, 3 BJ Botha, 2 Duncan Casey, 1 Dave Kilcoyne
Replacements: 16 Niall Scannell, 17 James Cronin, 18 John Ryan, 19 Dave Foley, 20 Shane Buckley, 21 Tomás O'Leary, 22 Ian Keatley, 23 Ronan O'Mahony
Referee: Gary Conway (Ireland)
Assistant Referees: Simon Rees, Martyn Lewis (both Wales)
TMO: Jon Mason (Wales)