The 29-year-old centre learned of his son Tito's death from his father Isikeli Ratulevu shortly before playing against Georgia on Saturday.

Tuisova helped Fiji turn around a 9-0 half-time deficit into a 17-12 victory against the Georgians, although he was sin-binned a minute from time due to a high tackle.

It leaves the Pacific Islanders requiring a point from their final Pool C match with Portugal on Sunday to progress to their third ever quarter-final - and first since 2007 - at the expense of the Australians.

Tuisova, who scored a try in the 22-15 pool win over Australia, will be a pivotal player for the Fijians in a likely quarter-final match-up with England, who they beat for the first time at Twickenham in August.

"With heavy hearts, we announce the passing of our beloved Tito Micgabraph Donzel Ratulevu," a statement in Fiji read last Friday.

"He is the son of Mr Josua Tuisova and Mrs Katarina Ladoge Ramoce.

"Affectionately known as 'Tito,' he peacefully departed after a prolonged battle with a debilitating illness in Lautoka hospital."

Fiji's head coach Simon Raiwalui said at a press conference on Tuesday it was a private matter.

"I will address that straight away," he said when the question was raised.

"Jos has asked respectfully it not to be discussed so it won't be discussed but keep it private."