Sculthorpe made a fairytale return to action for St Helens
St Helens: (6) 18
Tries: Gardner 2, Sculthorpe
Cons: Sculthorpe 3
Brisbane Broncos: (8) 14
Tries: Parker, Boyd
Pens: Parker 2
St Helens were crowned as the best club side in the world after edging out the Brisbane Broncos in a thrilling World Club Challenge encounter in Bolton.
Inspired by Ade Gardner's two tries and their returning captain Paul Sculthorpe, Saints sealed a famous win.
Sculthorpe, playing in his first match since September, scored a second-half try and made three superb conversions.
Brisbane led 8-0, but Gardner's try before half-time cut the gap and Saints battled ahead with 10 minutes left.
Having lost their last two Super League games to Harlequins and Wakefield, St Helens were given little chance against the NRL champions.
The Broncos, who had given themselves two weeks of preparation that included a warm-up match, got out of the blocks much the quicker.
Saints needed a magnificent tackle from Sean Long to stop Brent Tate going the length of the field after a high ball bounced into the Broncos player's hands.
It was only a temporary reprieve for Saints though as Gardner started his evening in horrible fashion, knocking a hanging high kick into Corey Parker's path for the Broncos' opening try.
Saints looked rattled, with knock-ons and sloppy passes costing them possession and territory, and Parker slotted a penalty on 11 minutes - after Matt Gidley's unnecessary spear tackle - for an 8-0 lead.
Sculthorpe ran onto the pitch for Mike Bennett on 21 minutes and it seemed to be just the boost St Helens needed.
For the first time, Saints were able to establish some pressure on the Broncos try line, but the Australian side's defence held firm.
St Helens had to produce a top-class defensive display
With the clock ticking down towards half-time, St Helens got a lucky break when Long's penalty to touch was ruled to have just made it despite Justin Hodge's leap into the air to prevent the ball going out.
From the resulting possession, Saints put together a high-class move to put Gardner in at the corner where he finished well, stepping inside Darius Boyd.
Sculthorpe slotted a tremendous conversion from the touchline to send Saints into the break with a spring in their steps.
Keiron Cunningham, who had not trained all week because of a hip injury, emerged for the second half, but two minutes after the kick-off Brisbane scored a controversial second try.
Boyd ran onto an inch-perfect Lockyer kick, but the officials had missed a blatant forward pass in the build-up.
The match turned into an arm-wrestle with both sides competing for every inch in the middle of the park.
But it was the Broncos defence which cracked first as a simple flat pass from Cunningham found Sculthorpe lurking to the right of the posts, and the returning skipper glided through to level the scores.
Gidley conceded a second penalty five minutes later, and Parker punished him again to edge the Broncos ahead.
But St Helens, driven on by a 23,000 crowd, were not to be denied.
After making a series of hard yards through their forwards, St Helens saw Long put up a steepling bomb.
The onrushing Gardner leapt high into the air to claim the ball over the static Broncos defenders and power over.
The score, and Sculthorpe's excellent conversion, put Saints ahead for the first time and they refused to let the Broncos back into the game despite a late spell of pressure.
St Helens: Wellens, Gardner, Gidley, Talau, Meli, Pryce, Long (c), Fozzard, Roby, Cayless, Gilmour, Bennett, Wilkin.
Replacements: Sculthorpe, Graham, Hargreaves, Cunningham
Brisbane: Hunt; Boyd, Tate, Hodges, Michaels; Lockyer (c), Perry; Carlaw, Berrigan, Civoniceva, Parker, Thorn, Carroll.
Replacements: Thaiday, Eastwood, Hannant, Ennis
Referee: Steve Clarke (Aus)