Wigan said farewell to a ground where they have found it so difficult to win in recent years with a victory that further entrenches them at the top of Super League.
The last-ever Good Friday derby at Knowsley Road saw Saints batter away for most of the second half without being able to undo the damage done in the first, as their rivals won on enemy territory for the first time since 2003.
"It was probably some good defence from them and some not-so-good play from us," said Saints' coach, Mick Potter, whilst his counterpart, Michael Maguire, praised the determination of a Wigan team carrying several walking wounded.
The GPW Recruitment Stadium, as it will end its life this autumn, has seen a lot more spectacular Good Friday games than this, although it was one that exemplified the intensity of the rivalry between the two clubs.
It was always Wigan who had the edge in the first half, starting with Pat Richards' third-minute penalty after a ball-stealing offence. There were limited chances after that, before Sean O'Loughlin led the charge for the first try. There was something appropriately nostalgic about the way Wigan muscled Saints off the ball, enabling the in-form O'Loughlin to pinch the ball from Scott Moore at the base of the scrum.
That set up a position from which O'Loughlin's pass was knocked down by Francis Meli's attempted intercept, and Darrell Goulding swooped for a messy but valuable try.
The second, five minutes before half-time, was largely self-inflicted from Saints' point of view. Maurie Fa'asavalu knocked on, Saints conceded a couple of penalties and, from the second of them, Iafeta Palea'asina barged his way over for the first try of his season – with some defenders looking as though they were expecting a kick for goal.
Richard extended Wigan's lead with his fourth goal early in the second half, but the game then looked like turning after Amos Roberts was sent to the sin-bin. The full-back was dispatched for one of a series of play-the-ball offences that blighted the afternoon, and Saints immediately took advantage, with Kyle Eastmond's kick into the arms of Ade Gardner followed by the young half-back's conversion from the touchline.
Just before Roberts returned, Tony Puletua forced his way over, but this time Eastmond missed the easier conversion. Saints went close when Meli's effort was ruled out for a forward pass, but Wigan held their nerve, with the help of a further goal from Richards.
St Helens: Pryce; Gardner, Gidley, Dean, Meli; Wilkin, Eastmond; Graham, Cunningham, Puletua, Flannery, Clough, Moore. Substitutes used: Roby, Hargreaves, Dixon, Fa'asavalu.
Wigan: Roberts; Goulding, Gleeson, Carmont, Richards; S Tomkins, Leuluai; Fielden, McIlorum, Prescott, Bailey, J Tomkins, O'Loughlin. Substitutes used: Palea'asina, Deacon, O'Carroll, Mossop.
Referee: B Thaler (Wakefield).