South Sydney edge North Queensland in Cairns thriller

South Sydney have registered their longest NRL winning streak in 29 years after edging North Queensland in a 21-20 thriller thanks to an Adam Reynolds field goal.

While Cowboys great Johnathan Thurston had his best game of the year and was instrumental in all of his side's points, it was his opposite number who proved the game-winner at Barlow Park in Cairns.

Reynolds snapped a 25m field goal with two minutes remaining before Thurston missed a chance to send the game into extra-time.

It extended the Rabbitohs' winning streak to eight games - their longest since 1989 and cemented their spot in second on the ladder.

Souths' win was soured after Greg Inglis suffered what was later confirmed as a broken thumb, ruling him out of Queensland's side for State of Origin III.

While his team pushed the second-placed Rabbitohs all the way, North Queensland coach Paul Green lashed his side for throwing the game away. He described Cody Walker's try before halftime as "soft" and rued their poor ball control after the break.

"I was really disappointed with the effort to be honest," Green said.

"I thought the game was there, we had the game won. There was just a couple of plays we didn't make when we had to.

"We lost the game because of it."

With Michael Morgan (biceps) missing, Thurston sought to take the game by the scruff of the neck.

The Cowboys were the better side in the first half with Antonio Winterstein and Gavin Cooper scoring after deft Thurston kicks.

South Sydney stayed in the game thanks to a controversial Reynolds try with the Cowboys remonstrating after George Burgess collided with Jake Granville to open up the hole for the Rabbitohs halfback.

However the Rabbitohs were also arguably hard done by after Dane Gagai was denied by the bunker for a Graham knock-on, despite the ball appearing to bounce backwards off his head.

A Walker try off a strong Sam Burgess offload reduced the Cowboys' lead to 14-12 at the break and winger Campbell Graham then crossed for the go-ahead try four minutes after the resumption.

It was Thurston who got his side back in front with a big play as he grubbered and Scott Bolton regained possession off a Souths deflection before Lachlan Coote snuck over.

The Rabbitohs showed why they are the best attacking team in the competition, scoring via Jennings before winning the game thanks to Reynolds.

"Reyno practices those kicks at training. After that first miss I knew he wouldn't go away from having another crack so we were quite fortunate. He did a good job," Souths coach Anthony Seibold said.

Souths prop Jason Clark will come under the scrutiny of the match review committee after he was put on report for a cannonball tackle.