Concussion rule puts five players in question for next week

FIVE players, two of them from the already injury-battered Newcastle Knights, will have to pass concussion tests this week before being cleared to play for their clubs in the second round of NRL fixtures.

Knights coach Wayne Bennett is struggling to name 17 fit players for Sunday's home clash with Canberra after play-making pair Kurt Gidley and Tyrone Roberts were both forced from the field against Penrith at the weekend following heavy collisions.

Administrators have cracked down on players returning to the field after being concussed this season, warning clubs they will be thoroughly investigated and punished if they allow concussed players to rejoin the game without a full clearance from the club doctor.

Gidley, Roberts, Todd Lowrie (Brisbane), Mitch Brown (Canterbury) and Liam Fulton (Wests Tigers) were all knocked out in games over the weekend. They were prevented from returning to the field by club doctors acting under new head-trauma guidelines introduced by the NRL.

The league's general manager of football operations, Nathan McGuirk, told APN yesterday the league was comfortable with how the process had worked throughout round one.

"Once we have evaluated how they operate over the first few rounds we will see if there are any operational aspects we need to refine moving forward," McGuirk said.

"Player safety and welfare is a priority for the game and it's important that the clubs have been so supportive of the new guidelines."

While Gidley and Roberts are some chance of playing at the weekend, the Knights will be missing representative fullback Darius Boyd who had scans yesterday on his injured hamstring and could be sidelined for three weeks.

Bennett's best option would be to shift talented backline utility Dane Gagai to fullback for the injured Boyd and finding a new centre.