Sydney Roosters five-eighth Luke Keary

Cooper Cronk could be in the Queensland Maroons coach's box plotting against Luke Keary after helping to play his Sydney Roosters halves partner into State of Origin contention for the NSW Blues.

While their match against Newcastle Knights at Allianz Stadium on Sunday night had been billed as the battle between Cronk and Mitchell Pearce - the veteran Blues halfback who left after the Test halfback's arrival at the club - Keary was the star of the show.

In just two matches alongside Cronk, he has proved to be one of the form playmakers of the Telstra Premiership and he finished Sunday night with a try, two try assists, one line break, one line break assistant and six tackle breaks in the runaway 38-8 win.

However, Cronk's influence on Keary was obvious with the Maroons veteran, who retired from the representative ranks after Australia's World Cup win in December, steering the Roosters around the park sublimely.

The 34-year-old had a hand in five of the Roosters' seven tries and scored another himself in a performance which underlined why the club was so keen to sign him from the Melbourne Storm.

Despite having Pearce under contract, Roosters coach Trent Robinson and chairman Nick Politis wanted Cronk when he became available last year because they believed he was a better chance of leading them to a premiership in the next two seasons.

The result of Pearce's first outing against a club he represented on 238 occasions since 2007 would appear to vindicate their decision.

To be fair to Pearce, he was forced to play most of the match without first-choice halves partner Connor Watson after the former Roosters utility dislocated his shoulder twice before coming from the field in the 20th minute.

In comparison, Cronk had Keary alongside him. But it could be argued Pearce also played next to the former South Sydney Rabbitohs five-eighth last season. However, only on occasions did Keary look as threatening then as he did against the Knights.

With Penrith Panthers halfback Nathan Cleary sidelined for 10 weeks with a knee injury and Parramatta Eels halfback Mitchell Moses having so far failed to recapture his World Cup form for Lebanon, Keary has emerged a front runner for NSW selection.

After helping to make him a better player, Cronk could be plotting against Keary in Origin as has been invited by Maroons coach Kevin Walters to sit in the coaching box during this year's series.

The new Roosters pairing made their first impact on the game in just the seventh minute when Cronk received the ball on the right side of the ruck and passed to Keary on the left for the 26-year-old to put Latrell Mitchell over for the opening try of the game.

Only a forward pass call against Cronk prevented another Roosters try for prop Sio Siua Taukeiaho in the 14th minute and a kick from the veteran playmaker resulted in a try to Jared Waerea-Hargreaves 10 minutes before half-time.

Keary scored off a Cronk pass in the 35th minute and he then raced onto a clever kick from his halves partner, which landed between the Knights defensive line and star fullback Kalyn Ponga to send utility Victor Radley over just before the interval.

Roosters halfback Cooper Cronk.
Roosters halfback Cooper Cronk. ©Gregg Porteous/NRL Photos

Cronk took control in the second half and what became a one-sided contest began with him picking up a loose ball 15 metres from his own line and throwing an overhead pass to centre Joseph Manu, who sent Blake Ferguson racing to the try line.

He then scored himself after regathering his own grubber, which was initially intended for Keary, before executing a pinpoint kick to Ferguson in full flight to score his second.

Pearce tried hard but his former teammates seemed to be aware of his tactics, with Manu blocking a grubber kick and Mitchell knocking down a pass in the first half.

Pearce laid on the Knights only try for fellow ex-Rooster Aidan Guerra by threading a grubber kick between Boyd Cordner and Dylan Napa in the 32nd minute. But he had no further impact on the scoring.