Ex-Wallabies star's advice to injury-prone rookie Suliasi Vunivalu

Suliasi Vunivalu is being encouraged to stay mentally strong by fellow code-hopper Lote Tuqiri after his Wallabies debut was put on hold once more due to a recurring hamstring issue.

The ex-Melbourne NRL winger has endured three separate hamstring injuries in his first season of rugby union, limiting his opportunities and resulting in him missing all six of Australia's tests in 2021.

Tuqiri, an NRL premiership-winning player who successfully switched codes and went on to make 67 appearances for the Wallabies, says Vunivalu overcoming repeated setbacks will be more about his mental state than his physical one.

"When he's playing I think Suli's been pretty good actually," Tuqiri told AAP.

"But, yeah, that's on him to get his body right.

"He's an athlete. He looks great. Mentally he's just got to try and overcome what's going on for him.

"Fingers crossed he can get over that and maybe feature later on in the Rugby Championship."

Vunivalu's unavailability for Sunday's test against world champions South Africa on the Gold Coast denies Wallabies coach Dave Rennie the Fijian-born flyer's aerial prowess and raw athleticism.

While wing isn't a particular issue for the Wallabies' depth, Tuqiri acknowledges the presence of Vunivalu would give Rennie a different type of player.

"Marika's (Koroibete) doing a great job on the other side," Tuqiri said.

"He (Vunivalu) just offers something different ... he's a tough bugger.

"He'll get in there and do the hard work.

"He'll get in there and be physical, not to say we haven't been physical, but he's not afraid of getting in the confrontation of that physical battle."