Queensland and Cowboys great Johnathan Thurston will undergo shoulder surgery, ending his State of Origin career and ruling him out for the rest of the 2017 NRL season.

Thurston battled bravely with the injury through Queensland's Origin II win, kicking the winning conversion in the Maroons' 18-16 win over New South Wales in Sydney, but will now be sidelined for some months.

"On Wednesday night I could still get through the game while the shoulder was pretty warm, and the next morning doing some tests I could lift my shoulder above my head and to the side, so they were encouraging signs," Thurston said.

"But obviously I got the scan and the news isn't good. The best decision for myself and the club is to get the op done.

"I thought I might have been able to pump one or two more games out.

"But the medical advice I've been given is that if I wanted to live a normal life after football, then I had to have the surgery."

Thurston's last act in a Queensland jersey was to kick the winning conversion in game II. ( AAP: Dan Himbrechts )

The injury will also rule Thurston out of Australia's World Cup campaign, meaning it is highly likely he has played his last representative game.

"I would love to [play in the World Cup] but I don't think that's a reality," he said.

Game III in Brisbane was set to be Thurston's Origin swansong, but his clutch game II kick will almost certainly now be his last contribution in a Maroons jersey.

Thurston said he was "comfortable" with his decision to walk away from rep football, and will not be looking to make an Origin comeback next year.

Queensland coach Kevin Walters said the Maroons would wait to see what happens over the next few NRL rounds before deciding on Thurston's replacement.

"We are very grateful to Johnathan, that he has put this team in the position that we are now able to go to Suncorp Stadium for a decider," Walters said.

"His efforts in game two were really above and beyond.

"It's obviously a big void to fill for the Maroons, but we have got some good options there available to us."

Thurston's Queensland team-mate Darius Boyd has already been ruled out of game III with a broken thumb.