Lewis suffered a dislocated shoulder after crashing into sign just metres from the deadball line while attempting to get on the end of a Robbie Farah kick at Langtree Park and will be sent home.
It was the only down side though of a solid day at the office for the Cup favourites, as Daly Cherry-Evans stepped in at halfback and Greg Inglis went to fullback as Cooper Cronk and Billy Slater were rested.
It was yet another top atmosphere for a World Cup clash, as 14,137 fans – mostly for Fiji – put up with cold and rain throughout.
Cherry-Evans set up two tries and scored one himself in an impressive performance from Australia against a more than decent Fiji line-up.
Other try scorers included Darius Boyd, Michael Jennings, Luke Lewis, Josh Morris and Luama Papalii on debut, while five-eighth Johnathan Thurston missed just one of his six conversion attempts.
Australia next take on Ireland, who were flogged 42-0 by England today, in their final pool game.
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