Hull KR coach Willie Peters questions Matt Parcell incident after Warrington Wolves loss

After racing into a 12-0 lead, Rovers – already without several spine players – saw Parcell forced off with a match-ending head injury just before half-time.

The Robins failed to recover from the setback as Warrington took control to claim a hard-earned win and extend their advantage at the top of Super League.

Peters expressed his frustration in the aftermath of an enthralling top-of-the-table clash.

"I haven't seen it but I'm not sure how you can just go down like that and be concussed if something hasn't happened," he said.

"There were some big calls there at different moments and that was a crucial point.

"I'd need to have a good look at it but if it is a deserving penalty, it's a big moment in the game.

"Matty seems to think it was a forearm but because there are no replays, we haven't been able to have a look at it.

"I don't know how you go down like that and be concussed without something happening; something has happened but I don't know what it was."

The result ended KR's six-match winning streak but they remain third on points difference.

Peters was left to rue a major turning point when Elliot Minchella was denied by Josh McGuire with Rovers seemingly one score away from killing the game.

"I thought we were up for it," said Peters.

"Warrington probably weren't anywhere near as effective as they were in the second half. They lifted and credit to them. Their line speed and intent was far better in the second half.

"We definitely played well in that first half. If Elliot Minchella scores that try and it's 18-0, who knows off the back of that.

"In terms of the way we competed and our effort, I can't fault them."