Wigan finished with a flourish to claim their eighth win in nine matches - and climb to third in the Super League table.
The win - in front of a crowd of 10,702 - nudged them ahead of Hull FC, who face Wakefield on Sunday.
Bevan French made his debut, Liam Farrell scored a double and Zak Hardaker struck a perfect six goals from as many attempts on an ultimately satisfying night for Adrian Lam.
It was a tired, but tight, contest for an hour in which the score was level 18-18 before Wigan moved through the gears in the last quarter to score three unanswered tries.
Three-time Grand Final-winning coach Shaun Wane was sat alongside executive director Kris Radlinski in the directors' box to see his old club strengthen hopes of return to Old Trafford.
As well as French's first appearance, Ben Flower and Joe Greenwood returned from injury - the trio replaced Jarrod Sammut, Romain Navarrete and injured Sean O'Loughlin - while Chris Hankinson was a direct replacement for Dan Sarginson, who was a late withdrawal.
Wigan had beaten KR twice in the previous two months - one by a drop-goal, another by a landslide.
By half-time, it appeared this would be one of the tense encounters as they were all square 12-12. But the hosts improved as the second-half unfolded and KR's resilience eventually melted.
It had started so well for Wigan, with George Williams piercing the line, turning the full-back and blazing away from the swarming cover to give them a 6-0 lead.
But Ryan Shaw locked the scores, sweeping over in the corner for a try he converted.
The seesawing nature continued, as Liam Marshall - a two-try scorer last week - crossed to atone for an error moments earlier. Hardaker again tagged on the extras.
The game fizzled and the loudest cheer was to mark Flower's return from the bench after several weeks on the sidelines with torn back ligaments.
There were some notable contributions - Oli Partington and Sam Powell, especially - but overall they lacked their usual verve and cohesion. In fairness to the Robins, they were spirited and performed better than many expected, especially once it emerged key player Danny McGuire wouldn't feature.
Another Wigan error - this time a forward pass - provided the Robins to draw level through Ben Crooks' converted try.
Farrell crashed onto Powell's short pass to help send Wigan 18-12 ahead early in the second-half.
Again KR replied, as Josh Drinkwater touched down his own bobbling kick to again draw level.
While Wigan should have done better to protect their line, the chance could be traced back to another error which invited KR into their territory.
But slowly, set for set, they began to resemble their normal selves as they asserted their authority to shut-out the game.
Joe Burgess squeezed in for the 100th try of his Wigan career before the hour-mark, the big-screen replay - a nice addition for the matchday experience - seeming to confirm suspicions of a missed forward pass in the build-up.
Burgess' reward was to be hooked to make way for new-boy French, who took his place on the left wing for the final quarter.
The ex-Parramatta crowd-pleaser had an early half-chance, jetting away but then tripping as he chased his own kick, before Tony Clubb thundered over to snap the seesawing nature of the game and open up a 30-18 lead.
And Farrell had the final say, angling and weaving over for his second try to wrap up the two points.
Wigan are next in action at home to Warrington next Friday.
Wigan: Hardaker; Marshall, Hankinson, Gildart, Burgess; Williams, Leuluai; Clubb, Powell, Partington, Isa, Farrell, Smithies. Subs: Greenwood, French, Flower, Byrne.
Hull KR: Quinlan; Shaw, Crooks, Keinhorst, Dagger; Lewis, Drinkwater; Masoe, Atkin, Murray, Tomkins, Hauraki, Hadley. Subs: Trout, Mulhern, Litten, Harrison.
Referee: Chris Kendall