Tyson Frizell may enter State of Origin I under an injury cloud after failing to finish St George Illawarra’s 16-9 NRL defeat by Cronulla due to concussion.

Frizell was knocked out late in the first half after a sickening head clash with Josh Dugan, before being ruled out for the rest of Sunday’s game.

The Dragons star was considered a certainty to be included in the NSW Origin team that was to be announced after the match in Wollongong.

He was one of three first-half injuries that whittled the Dragons to 14 men for the entire second period, along with James Graham and Tim Lafai (ankle).

The injury toll cruelled any hope the Dragons had of holding onto a one-point halftime lead, and they slumped to a fifth straight defeat.

The win for the Sharks came on the back of the electric return by Matt Moylan, who had a hand in two tries, and a Bronson Xerri hat-trick of tries.

Moylan’s inclusion added plenty of polish in a slick combination with Chad Townsend and Kyle Flanagan that thoroughly outplayed their counterparts.

It didn’t take long for Moylan to have an impact, swerving to take an out-ball and creating the overlap for Xerri to post first points.

Dragons halfback Ben Hunt should’ve equalised only to drop the ball over the line, but Cameron McInnes saved his blushes by charging over in the 32nd minute.

Sosaia Feki matched Hunt’s bombed try when he collected a ball while standing on the sideline with the tryline open.

That opened the door for Hunt to give his team a one-point lead at the break with the first field goal of his career in front of the 14,586 WIN Stadium crowd.

But it wouldn’t take long for their lack of troops to tell on the scoreboard, beginning with Xerri grabbing his second in the 46th minute.

Sharks second-rower Kurt Capewell beat Jordan Pereira to a second-tackle Flanagan kick, and picked it up for Xerri to score.

The Sharks rookie then completed his first career hat-trick when he took a no-look Moylan pass in the 60th minute, before Blayke Brailey scored on the siren.