Sam Tomkins' late penalty ultimately proved decisive as Wigan tightened their grip on second spot.
With so much attention on off-the-field issues this week - future coaches, John Bateman's exit, George Williams' comments - the focus switched to matters on the pitch for Wigan's opening Super-8s game.
Shaun Wane's successors, Adrian Lam and Shaun Edwards, watched from the directors' box flanking chairman Ian Lenagan.
And they witnessed the proverbial game of two halves as they built-up a 20-0 lead with a slick, dominant display - only to let Castleford go within a whisker of snatching a win which would have seen them leapfrop into second.
As it was, the Warriors - playing their first match in two weeks - have now opened up a three point gap on the chasing pack.
Despite this being one of the more attractive fixtures, there was a low-key build-up and atmosphere - perhaps because of the fact fans were given just nine days' notice about the game under the Super-8s concept.
As expected, Wane handed a debut to academy prop Oliver Partington and recalled fit-again George Williams - who had made headlines earlier in the day with his admission he wants to move to the NRL.
Thomas Leuluai started his first match this season at half-back, with Sam Powell switching to hooker, and Ben Flower figured in his 150th match for the club.
Castleford, still without Luke Gale, knew a victory would see them leapfrog the hosts into second spot.
Wigan made the brighter start and opened the scoring in the fifth minute when Williams spotted space on Cas' right edge and threaded a ball through which Liam Marshall dribbled on before touching down.
Sam Tomkins was unable to convert, but moments later put Romain Navarrete through a gap to launch another raid. That attack was repelled but the action remained in the Tigers' half and, with them turning over possession three times, there was a sense of inevitability when Wigan extended their lead when Gabriel Hamlin hammered his way through.
Tomkins tagged on the extras to make it 10-0 before Marshall went close to extending their lead, only for a try to be ruled out by the video referee. Cas' themselves were also denied by the TV official after Joe Wardle went close.
And after both sides lost key players - Tomkins and Adam Milner - the Warriors powered ahead, Dan Sarginson angling through a jagged defence to open up a 14 point gap. Replacement Morgan Escare was off-target with the conversion attempt but hit a goal minutes later after Ryan Sutton had marked his return from injury by muscling over the whitewash.
Partington, an ex-Orrell St James junior, came off the bench and made some solid contributions in the middle - and was later involved in a heated exchange with Milner.
The half-time break disrupted the flow of the match, with Cas' roaring back into the contest through Jake Trueman's early, unconverted try.
A high-tackle on Powell allowed Escare to strike a penalty which nudged the hosts into a 22-4 lead.
But the Tigers remained on the offensive as James Clare out-leapt Marshall to touch down in the corner.
Wigan still had a 12-point lead but they appeared the side on the ropes. And when Paul McShane touched down a kick - the video referee ignoring Leuluai's protests he was taken out off the ball - it closed the gap to a fragile six points.
Escare rattled the woodwork with a drop-goal attempt before being replaced by Tomkins for the final quarter-of-an-hour.
But when Joe Greenwood was collared high by Mike McMeeken, it presented Tomkins the chance to kick a penalty - which settled their nerves.
Mitch Clark grabbed a consolation as the hooter sounded, but Wigan had done enough to hang on to victory - they head to Catalans next Saturday.
Wigan: S Tomkins; Davies, Isa, Sarginson, Marshall; Williams, Leuluai; Navarette, Powell, Flower, Greenwood, Bateman, Hamlin. Subs: Escare, Clubb, Sutton, Partington.
Castleford: Eden; Gill, Wardle, Shenton, Clare; Ellis, Trueman; Watts, McShane, Sene-Lefao, Holmes, McMeeken, Massey. Subs: Webster, Moores, Milner, Clark.
Referee: James Child
Starman: Sam Tomkins