Updated September 22, 2018 22:11:14

Photo: Daniel Tupou scored the first of three Roosters tries as they beat South Sydney 12-4 in the preliminary final at the Sydney Football Stadium. (AAP: Dan Himbrechts)

Cooper Cronk is racing the clock to be fit for the NRL grand final after injuring his shoulder in the Sydney Roosters' 12-4 NRL preliminary final win over South Sydney.

Cronk injured his left shoulder as he took a field goal attempt on the stroke of half-time on Saturday night and was little more than a passenger the entire second half.

In front of a record crowd of 44,380 in the final game at the Sydney Football Stadium before it's redeveloped, the minor premiers won through to their second grand final in six years.

Former Queensland and Australian playmaker Cronk was brought to Bondi Junction to deliver the premiership that Mitchell Pearce couldn't and now he's in doubt to face his former club Melbourne in the season decider.

Cronk was injured after being crunched by Adam Reynolds as he attempted to break a 4-4 deadlock and got up clutching his left shoulder.

After the Roosters physios worked on him at half-time, he was visibly hobbled after coming back out and could barely raise his arm.

At times he could only put his body in front of opposition ball carriers, hoping his teammates got there to help out.

In the end, the Roosters' goalline defence proved the difference, with Souths enjoying 30 tackles inside the opposition red zone but unable to cross for a try.

The Roosters went ahead 8-4 when Joseph Manu, despite the attention of Greg Inglis and Alex Johnston, popped a beautiful pass in traffic to send Blake Ferguson over.

The Rabbitohs were clearly targeting Cronk, with Junior Tatola smashing him after he had passed the ball.

However, Sio Siua Taukeiaho couldn't convert the two points from the resulting penalty.

From the next set the Roosters iced the game after centre Paul Momirovski, who was a surprise late inclusion for the suspended Latrell Mitchell, crossed for the decisive try.

When Luke Keary lofted a bomb, Campbell Graham failed to reel it in and Momirovski, who was playing the second game of his career, pounced.

The Roosters will receive a big boost going into the grand final, with Mitchell and prop Dylan Napa to return.

Roosters skipper Jake Friend will come under the attention of the match review committee for a tipping tackle on Greg Inglis in the first half.

AAP

Topics: nrl, rugby-league, sport, australia, nsw, sydney-2000

First posted September 22, 2018 19:19:39