NSW five-eighth James Maloney has backed former Sydney Roosters teammate Mitchell Pearce for the Blues halfback role if Nathan Cleary is ruled out of the State of Origin decider.

Cleary will undergo scans after the Blues return to Sydney on Monday night but is considered extremely unlikely to be fit for the July 10 clash at ANZ Stadium after being unable to return in the second half of the 38-6 triumph in Perth due to an ankle injury.

Maloney hopes his Penrith halves partner recovers in time to help the Blues try to retain the Holden State of Origin shield but if not, he believed Pearce would comfortably slot into the role.

The duo played alongside each other in the Roosters' 2013 Telstra Premiership-winning team and were the NSW scrum-base pairing in the 2013 and 2017 series.

Pearce had initially been Blues coach Brad Fittler’s first choice to partner Cleary in Sunday night’s match at Optus Stadium but Maloney got the call-up after the Knights veteran ruled himself out with niggling injuries.

"There was talk he would be here for Origin II so he wouldn’t be out of place and I said when there was a lot of talk that Mitchell would there that Mitchell would be good for Nathan," Maloney said.

"If he gets picked, we know each other’s game so if they go that way, or whoever they pick, we will go in and get the job done."

Maloney said he realised Cleary was injured when he asked him to take over the goal-kicking duties after centre Tom Trbojevic scored the second of his three tries in the 34th minute.

Fittler credited Maloney for steering the Blues to victory after delivering a half-time speech in which he told his teammates not to let Queensland off the hook as they did in Origin I after leading 8-0 at the interval before losing 18-14.

He said the emphasis had been on defence and was pleased the Maroons' only points came from a first-half penalty try awarded to Will Chambers after Jack Wighton impeded his run for a kick in the in-goal area.

"I suppose I sat at home and watched NSW go in front in game one so we wanted to make sure [the players knew] the job wasn’t done," Maloney said.

"We needed to keep playing, we needed to control everything and go after them. We wanted to not let them run through us and they got one try from an escort try so they didn’t break our line once and that was something we talked about.

"I think it was a game where everyone just did their role and did it really well. There was a lot of different moments, I thought the first half was really well set up. We managed to control where we gave them the ball and I thought our middles really attacked them defensively.

"On the back of all of that towards the end we kept playing footy and we wanted to keep attacking their edges."

Maloney threw the final pass for Tyson Frizell’s 19th-minute try and put up the bomb which led to Tom Trbojevic's first try after leaping above Queensland fullback Kalyn Ponga. He also peeled off a 40/20 kick and two forced goal-line drop outs.

"Tom is a top quality player and he puts himself in position to make plays like that," Maloney said. "He has obviously got a heap of ability but he has also got a heap of guts.

"He does it time and time again. That’s why I had no doubt when he was available he was straight back in, he was huge last year and he is made for this arena."