Tony Smith refused to blame the officials for missing two forward passes in the build-up to Wigan's match-turning try.
The game was level 18-18 on the hour-mark when Joe Burgess squeezed over for his 100th touchdown for the club.
Wigan then powered on, scoring two further tries to claim a 36-18 win against Hull KR.
Video replays appeared to confirm two forward passes in the build-up to Burgess' try.
Robins coach Smith admitted it was a turning point but said: "They were forward - but this isn't a whinge.
"I'm not complaining about it - we made more mistakes than any official tonight. It's a tough job."
Smith admitted he "absolutely" rested key player Danny McGuire to protect him for next week's game against Wakefield.
His side, battling against the threat of relegation, gave a good account of themselves in the first-half when they were level 12-12.
"I'm proud of the effort we put in but we made too many crucial errors and some of our game-management wasn't quite right," he added.
"We contributed to our own downfall, rather than being bullied or out-played."