The damaging Queensland No.13 missed Sunday's third-round clash with the Jaguares after hurting himself while attempting a tackle in training.

It is the second serious setback in as many seasons for the 19-year-old, after a second-round foot injury had ruined his 2019 campaign.

All up, he has played less than four matches in two seasons for the Reds, but had still managed to feature in three World Cup games, despite a separate hamstring injuring delaying his inevitable Wallabies debut.

Petaia rocketed into the Wallabies' starting line-up in the Cup quarter-final against England and was one of the side's best in Australia's most-recent Test.

But, with a 20-week rehabilitation period ahead of him, his place in the side for July's Tests against Ireland is is serious doubt.

He might set his sights on Townsville's Test on July 18 against Fiji, while the Bledisloe Cup and Rugby Championship follow from August-October.

With a target on his back to begin the season, Petaia was kept quiet in the first two games, but his absence is still a massive blow for the winless Reds (0-3) before Saturday's home opener against the Sunwolves.

However, the performance of his replacement Hunter Paisami, voted man of the match by his teammates in the loss to the Jaguares, is some solace for coach Brad Thorn.

Paisami did his best to replicate departed captain Samu Kerevi's straight running, busting through to set up one try and almost score one himself as the Reds burst to a 24-7 lead only to lose 43-27.

Former No.10 Hamish Stewart has re-invented himself this season as a hard-nosed centre. With James O'Connor starring at five-eighth in Argentina, Jock Campbell, Bryce Hegarty and Isaac Lucas are also backline options this weekend for Thorn.

Australian Associated Press