Former Wallabies wing Wendell Sailor is backing Israel Folau to be the greatest dual international of the professional era.
Sailor, who, like Folau, also represented Australia in rugby league, believes, England's 2003 Rugby World Cup winning wing Jason Robinson and Sydney Roosters stalwart Sonny Bill Williams, who hoisted the Webb Ellis Cup with New Zealand in 2011, presently share the mantle.
But after watching Folau equal Lote Tuqiri's all-time record for scoring the most tries for Australia in a calendar year during a superb 15-Test debut season, Sailor thinks the Waratahs utility back will have emulated Robinson and Williams by the end of his career.
Tuqiri, Sailor and fellow rugby league convert Mat Rogers represented the Wallabies in 149 Tests and amassed 57 tries, but Sailor feels 24-year-old Folau has already eclipsed all three as Australia's leading dual international.
"I think Israel, he's mixed a bit of everything," Sailor told AAP.
"He's taken what Lote's done, what I've done, Mat Rogers ... and Israel even though he's a by-product of that, I just think Israel's taken it to a new level now.
"Jason Robinson, Sonny Bill have been good, but I think he can nearly be better than all of those guys.
"He's only 24 or 25 or something. He can probably go to a whole new level."
Folau is youngest player, at 18, to represent Australia in a rugby league Test and scored on debut for both the Kangaroos and the Wallabies.
"His debut for the Wallabies saw him scoring a memorable brace against the touring British and Irish Lions in Melbourne earlier this year.
Sailor believes the code-hopper's tough two-year stint in the AFL with Greater Western Sydney played a significant role in his rapid rise in rugby.
"Just his confidence, I think going to AFL has helped him because from league he was at the heights of his stuff and then when you go to AFL you have to learn new stuff," he added.
"And he was in reserve grade a bit and getting ripped into a bit about not being that good at that level. I think it just shows that hunger.
"His switch (to rugby) was amazing. They were playing against the British lions - that can't be easy to do, but he was our best player and was nearly the best player through the series.
"I'd like to see him come back to league at some stage, but (after) a few more years in rugby and I'm happy he's going well because I know he got kicked a bit when he went to AFL and he showed what a class act he is."