Rebels secure Mafi deal
Tongan-born 26-year-old Mafi made four appearances for Japan, including scoring two tries, at the 2015 World Cup and played a crucial role in the historic 34-32 victory over the Springboks by providing the winning pass.
Rebels coach Tony McGahan welcomed the addition of 112kg Mafi to a back row already featuring hard-hitting Wallaby Sean McMahon.
"Amanaki will compliment our back row very well through his powerful game in the contact area," McGahan said.
"As we saw at the World Cup, Amanaki makes his presence felt' whether he's starting the game or off the bench."
Mafi is currently playing with NTT Communications in Japan and will join the Rebels squad at the end of the Top League Season.
In 2016, he joined Bath on a short term contract and made immediate impact with four tries in his first four matches.
He has been a standout player in Japan with selection in the All Japan Top League's Best XV for the last two seasons.
Mafi, who made nine international appearances for Japan including the most recent series against Scotland, said he was excited about the opportunity to play Super Rugby in Melbourne.
"I'm really grateful for this opportunity with the Rebels to represent my company NTT Communications in Super Rugby," Mafi said.
"Super Rugby has been a long term goal and I can't wait to arrive and test my skills against the world's best players.
"Melbourne is a great city and it will be a privilege to be a part of the Rebels team."
