Former code-hopping star Sonny Bill Williams has revealed he believes Joseph Manu should be allowed to head to rugby union, and that it will make him a better player as a result.

Manu was linked earlier this week to a short-term switch to Japanese rugby at the end of his current deal with the Sydney Roosters, that expires at the end of 2024.

Playing a single season in Japan could net Manu, who has played predominantly in the centres for the Roosters but has grand ambitions of being a fullback, north of a million dollars per season.

He would then return to the NRL about halfway through the 2025 season, likely with the Roosters to continue his career in the 13-man game.

Some eyebrows have been raised over the potential of the move and how it relates to the NRL's salary cap, but Sonny Bill Williams told The Sydney Morning Herald that Manu being an elite player means he has earnt the right and chance to explore other options.

โ€œWhen you're an elite player like Joey is, that's what you can do,โ€ Williams told the publication.

โ€œAs long as it's done respectfully, he deserves a chance to see what's there for himself.

โ€œI'm proud of him for stepping out there and doing his thing. When you have that talent, that talent deserves to be seen.

โ€œI think it'll be good for Joey, and he'll come back with a really enhanced skill level โ€“ that's what I found from my time [in Japan]. It'll be such a good experience for him, and stepping out of his comfort zone, that should be applauded.โ€

The NRL are yet to make public comment on the potential of a move to Japan for Manu and whether or not it would be allowed, although precedent exists after the code blocked Benji Marshall from a short-term move to the 15-man game during his career.

Manu, who the Roosters are confident of keeping, also has interest from rival clubs and a big-money offer on the table from the St George Illawarra Dragons to change clubs from the start of 2025.

The 27-year-old has been earmarked as the long-term replacement to James Tedesco at fullback for the Roosters.