Williams' rookie teammate Nehe Milner-Skudder spent time playing for the Bulldogs in the NYC before returning to NZ to play rugby for Manawatu and the Hurricanes. (AAP)
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Burgess
Sam Burgess is the most recent NRL convert to rugby and was a much-criticised inclusion in England's World Cup squad.
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Burgess
Of course, the Clive Churchill Medallist led South Sydney to a drought breaking NRL premiership in 2014 despite breaking a bone in his face in the first tackle of the grand final.
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Burgess
He has played two games for England in warm-up games at inside centre despite spending a lot of time in the back row for his club side, Bath.
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Folau
Israel Folau's journey in professional sport began at the Melbourne Storm as a 17-year-old in 2007. The then-winger won the NRL premiership with the Storm that year. He also represented Queensland in Origin and the Kangaroos.
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Folau
He moved to the Broncos in 2009 to be closer to his family in Queensland.
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Folau
Folau dropped a bombshell by announcing that he was moving to AFL expansion club the Greater Western Sydney Giants on a lucrative deal. He struggled with AFL, playing only 13 games in a solitary season in 2012.
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Folau
He ended his unhappy time in Australian rules to move to the Waratahs for the 2013 season. He was selected for the Wallabies immediately before starring as NSW won the Super Rugby title in 2014.
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Folau
He has quickly become the face of his third professional rugby code and is one of the key weapons for the Wallabies as they bid for an historic third World Cup.
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Sonny Bill
All Black Sonny Bill Williams left the NRL for rugby in infamous circumstances in 2008. He walked out on the Bulldogs in the middle of the NRL season and jumped on a flight to France.