The NRL has issued an official warning to Titans co-captain Kevin Proctor after his New Zealand teammate and ex-schoolmate Jordan Rapana alleged he was the victim of a "squirrel grip" during Gold Coast's stirring opening round win.

Proctor, reinstated alongside Ryan James as one of the Titans' two on-field leaders this year, was the subject of a bizarre complaint from Raiders winger Rapana, who got up out of a second half tackle agrily protesting with his opponent and the referees.

Warning: Kevin Proctor appears to execute a 'squirrel grip' on the Raiders' Jordan Rapana. Credit:Fox Sports

He pointed to his groin area and asked for intervention from the officials with replays showing Proctor had lodged his right arm between Rapana's legs in a tackle also featuring James.

Proctor wasn't charged by the NRL's match review committee, but it swiftly sent a letter to the Titans on Monday morning warning the 29-year-old over his conduct.