Connacht moved level with Scarlets at the top of the PRO12 table, defeating the Welsh side 30-17 at the Sportsground.
The visitors did not look like their normal selves, and conceded two first half tries without reply, before putting up a second half comeback which was halted with two yellow cards in the space of three minutes.
The bonus point win moves Connacht behind Scarlets on number of matches won only.
Two tries from Jake Heenan, and one apiece from Dennis Buckley and Rodney Ah You, were enough to hand the Irish team the maximum five points.
Connacht came out of the blocks ferociously, and had a penalty awarded just a couple of minutes into the game, but Jack Carty's effort hit the post and rebounded back into play.
Carty did not have to wait long to make amends, with the home side awarded another penalty four minutes later, and he made no mistake this time.
The hosts extended the lead further with a well-earned try. The driving maul got over the line, with Heenan claiming the final touch. Carty could not convert, with his effort once again hitting the post.
And on the brink of half-time, Heenan grabbed his – and Connacht's – second try of the game. It came from a maul forward from the five-metre lineout, with Scarlets not strong enough to stop the ball crossing the line. Once again, Carty's kicking was called into question as he missed the chance to add the extras.
That was a minor problem, with the Irish side taking a 13-0 lead into the break.
The second half started in complete contrast to the first 40 minutes, with Scarlets making short work of that seemingly unassailable lead.
First, Aled Thomas scored a penalty three minutes into the half, and DTH van der Merwe went over less than sixty seconds later for the visitor's first try of the day. Thomas converted, and Connacht's lead was reduced to three points.
But, in a matter of minutes, that hard work was undone for the visitors, with a Carty penalty sandwiched in-between two yellow cards for Scarlets. Phil John and Tom Price were the culprits.
It didn't take long for the hosts to take advantage. A driving maul could not be defended by the dilapidated away defence, allowing Buckley to crash over. Carty added the extras, making it 23-10.
Minutes after coming into the fray, Ah You grabbed Connacht's fourth try of the game, spotting a gap in the defence, and Carty's simple conversion finally put the game beyond the Welsh side.
That did not stop the visitors from trying their best, and Gareth Owen went over in the corner. Thomas converted, but Scarlets latest comeback ended their, with Connacht holding out for the 30-17 win.
Tries: Heenan 2, Buckley, Ah You
Cons: Carty 2
Pens: Carty 2
Yellow Card: Heffernan
Tries: Van der Merwe, Owen
Cons: Thomas 2
Yellow Cards: Price, John
Connacht: 15 Tiernan O’Halloran, 14 Danie Poolman, 13 Robbie Henshaw, 12 Bundee Aki, 11 Matt Healy, 10 Jack Carty, 9 Caolin Blade, 8 Eoghan Masterson, 7 Jake Heenan, 6 John Muldoon (c), 5 Aly Muldowney, 4 George Naoupu, 3 Finlay Bealham, 2 Tom McCartney, 1 Denis Buckley
Replacements: 16 Dave Heffernan, 17 Ronan Loughney, 18 Rodney Ah You, 19 Ultan Dillane, 20 James Connolly, 21 Ian Porter, 22 Craig Ronaldson, 23 Rory Parata
Scarlets: 15 Liam Williams, 14 Tom Williams, 13 Gareth Owen, 12 Hadleigh Parkes (c), 11 DTH van der Merwe, 10 Aled Thomas, 9 Rhodri Williams, 8 Morgan Allen, 7 Will Boyde, 6 Aaron Shingler, 5 Lewis Rawlins, 4 Tom Price, 3 Rhodri Jones, 2 Ryan Elias, 1 Phil John
Replacements: 16 Kirby Myhill, 17 Dylan Evans, 18 Peter Edwards, 19 Jack Jones, 20 Tom Phillips, 21 Connor Lloyd, 22 Steven Shingler, 23 Michael Collins
Referee: Ben Whitehouse (Wales)
Assistant Referees: Gary Conway (Ireland), Eddie Hogan-O'Connell (Ireland)
TMO: Dermot Moloney (Ireland)