Jordan Turner ensured a treble of wins against Warrington for St Helens in 2015
|Warrington (6) 14|
|Tries: Currie, Penny Goals: O'Brien 3|
|St Helens (8) 20|
|Tries: Roby, Masoe, Turner Goals: Walsh 4|
Jordan Turner's late try moved St Helens to the top of Super League with victory against a Warrington side whose top eight place is in mild jeopardy.
Saints are now a point clear of Leeds, who can move back to the top with a win against Salford on Friday.
Sixth-placed Warrington can still mathematically be caught by Hull KR, who play rivals Hull FC in round 22.
James Roby put Saints ahead before Ben Currie and Kevin Penny struck, but Mose Masoe and Turner crossed to seal it.
Champions Saints beat Huddersfield in similarly dramatic circumstances last week, and their stamina was needed after the Wolves fought back before half-time.
For the home side, defeat continued their disappointing home form against Saints, with one win since moving to the Halliwell Jones Stadium from Wilderspool in 2004.
St Helens have beaten Warrington on all three occasions the two have met this season, with a 32-24 win at Langtree Park in March added to the 20-16 Magic Weekend victory at St James' Park in May.
The pressure on both sides for the points made for a feisty game that was littered with penalties and included a team warning for the home side in the first half.
Saints made the better start in a high-energy first quarter, scoring when James Roby grounded the ball from dummy-half on the back of repeat sets.
Luke Walsh penalised further Wolves infringement from the tee to establish an 8-0 lead but Warrington grew in dominance toward the end of the half.
Ryan Atkins swung a pass into touch when well-placed and Anthony England had a score chalked off for a forward pass before a sliding move to the left put Currie in just before the half-time hooter.
Tony Smith's side moved ahead for the first time when Kevin Penny swooped on a loose pass by Walsh to score, but a bulldozing run by Masoe took him under the sticks to restore the lead.
Twice Saints prevented Wolves from crossing for tries, with Joe Philbin and Ryan Atkins denied before Turner wrapped up the points, touching down on the left in the last moments.
Warrington coach Tony Smith:
"We've played better tonight than in many of the games we've won this year. I'm disappointed to lose but it was a super try to win it and a great game of rugby league. I don't mind conceding those tries because they take some scoring.
"It was the soft tries by James Roby and Mose Masoe that hurt you. Other than those, our defence was really good and our physicality was great.
"We gave ourselves a real chance and, if we play with that sort of spirit in defence and with a few improvements to our attack, I think we'll win a few more games this year."
St Helens coach Keiron Cunningham:
"I'd have taken the draw. The game probably didn't deserve a loser. Both teams were great for periods of the game and defences were good. Warrington are so quick down the middle, they've got four dummy-half runners basically coming at you and you've just got to survive.
"Fortunately I saved a few subs up for the second half and they did a good job. I knew we would get a crack at something and I told my players they would always get an opportunity to win the game but we left it quite late again.
"I'm pleased with the two points but the performance was the biggest thing for me. We found a way to win the game despite being on the back foot for large portions of the game. All credit to Jordan Turner because that left side had taken some flak in recent weeks and I thought it was very poignant that he puts the ball down to win the game."
Warrington: Russell; Ormsby, Ratchford, Atkins, Penny; O'Brien, Myler; Hill, Clark, Sims, Westwood, Currie, Harrison.
Replacements: Dwyer, Asotasi, England, Philbin.
St Helens: Quinlan; Dawson, Percival, Turner, Swift; Burns, Walsh; Amor, Roby, Walmsley, Greenwood, Wilkin, Flanagan.