Corey Harawira-Naera will be the Raiders' first 18th man under the NRL's new interchange rules, which kick into effect this round as Canberra takes on the red-hot Penrith Panthers in Sydney. It edges Harawira-Naera closer to his first NRL match since a drink-driving conviction and two-game ban, but will most likely leave the ex-Canterbury Bulldog sitting on the pine for 80 minutes. The 18th man will be activated should three players in his side fail head-injury assessments during the course of a match, or if a player is forced to leave the field due to foul play and the perpetrator is either sin binned or sent off. Otherwise, Raiders coach Ricky Stuart will not be able to inject Harawira-Naera into the contest. "It's a matter of balancing utility value," Stuart said.