Scarlets reclaim top spot after edging Connacht
Connacht were heading for the win that would arrest their three-game losing streak in the league after Jack Carty struck late on.
But instead Scarlets completed a dramatic turnaround after finding themselves ten points down at one point in the first half.
The early blows were traded in the kicking game before Connacht lost Bundee Aki to the sin-bin for a shoulder tackle on Regan King.
The Irish province managed to staunch the resulting attack, as Niyi Adeolokun and Craig Ronaldson forced Scarlets into touch, before they won a penalty of their own.
Connacht began to gather some momentum and, after Kieran Marmion's pick-and-go breached Scarlets' 22,
Eoghan Masterson touched down over the line – only for the TMO to adjudge that the flanker had knocked on instead.
Morgan Allen relieved the pressure after breaking from the resulting scrum but Connacht now had their full complement back with the return of Aki.
The first points of the match finally arrived in the 22nd minute as Ronaldson stepped up off the tee after King was pinged – and yellow-carded – for killing the ball.
But they didn't have to wait so long for the next score, Matt Healy turning on the afterburners from his own 22 to dot down before Ronaldson split the posts with the extras.
With King back in the fold, Aled Thomas cut the deficit down to seven points after an offside drew a penalty in the 35th minute.
Then Hadleigh Parkes pulled off a brilliant tackle to deny Healy his second, forcing the ball to slip away from the wing before the wing could apply the touch down.
But Scarlets attacked the second half with fresh vigour and when Connacht pulled down a line-out, Thomas scored from the tee again.
And after a superb Michael Collins charge down, John Barclay churned out a strong carry before Evans stormed over out wide.
Thomas' conversion edged Scarlets ahead but only temporarily as they were penalised for blocking and Ronaldson levelled things up.
The game increasingly opened up but Scarlets were riding the crest of a wave, and on the hour-mark full-back Collins sped over after an initial surge from King.
This time Thomas failed with the extras, and some inspired work from Aki saw Connacht carry the ball into Scarlets' 22 soon after.
A penalty fell Connacht's way at the breakdown however and Carty reduced the arrears to two.
The tension could be felt by both sides in the final ten minutes and Carty looked to have won it for the visitors after Scarlets gave away a penalty ten metres out.
But the game was turned on its head once again when Ronan Loughney was sin-binned for a tip tackle in a ruck and Shingler, a second-half replacement decided a nail-biter with two minutes to go.
The scorers:
For Scarlets:
Tries: S Evans, Collins
Con: Thomas
Pens: Thomas 2, Shingler
For Connacht:
Try: Healy
Con: Ronaldson
Pens: Ronaldson 2, Carty 2
Yellow cards: Ronan Loughney (Connacht, 8), Ronan Loughney (Scarlets, 23), Ronan Loughney (Connacht, 78)
Teams:
Scarlets: 15 Michael Collins, 14 Steff Evans, 13 Regan King, 12 Hadleigh Parkes, 11 DTH van der Merwe, 10 Aled Thomas, 9 Aled Davies, 8 Morgan Allen, 7 John Barclay, 6 Aaron Shingler, 5 Lewis Rawlins, 4 Tom Price, 3 Samson Lee, 2 Ken Owens (c), 1 Rob Evans
Replacements: 16 Ryan Elias, 17 Phil John, 18 Rhodri Jones, 19 Maselino Paulino, 20 Rory Pitman, 21 Rhodri Williams, 22 Steve Shingler, 23 Steff Hughes
Connacht: 15 Tiernan O'Halloran, 14 Niyi Adeolokun, 13 Bundee Aki, 12 Craig Ronaldson, 11 Matt Healy, 10 Jack Carty, 9 Kieran Marmion, 8 Eoghan Masterson, 7 Jake Heenan, 6 John Muldoon (c), 5 Andrew Browne, 4 Ultan Dillane, 3 Nathan White, 2 Tom McCartney, 1 Finlay Bealham
Replacements: 16 Dave Heffernan, 17 Ronan Loughney, 18 Rodney Ah You, 19 Aly Muldowney, 20 Sean O'Brien, 21 Ian Porter, 22 AJ MacGinty, 23 Rory Parata
Referee: Marius Mitrea (Italy)
Assistant referees: Gwyn Morris (Wales), Stuart Kibble (Wales)
TMO: Paul Adams (Wales)
Source: @PRO12rugby