Melbourne fans are set to see a familiar face in the Kangaroos No.1 jersey for the opening World Cup match at AAMI Park on October 27.

Australia coach Mal Meninga has admitted the fullback position is Billy Slater's to lose.

Melbourne's Slater was this week named by selectors at fullback in the inaugural Kangaroos Origin Merit Team, based on performances from the State of Origin series.

And Meninga on Tuesday used the 100-day countdown to the match against England to confirm Slater's favouritism.

The proclamation came exactly two months after Meninga said he agreed with the decision to overlook the 34-year-old for State of Origin I, when Slater was surprisingly omitted after his long absence from the NRL with two shoulder reconstructions.

However, Slater's dazzling form in games two and three to help the Maroons secure a series win was behind his backing ahead of Kangaroos incumbent fullback Darius Boyd.

Brisbane skipper Boyd switched to the centres to accommodate Slater in game two and was out injured for the decider.

It has been three years since Slater played the last of his 25 Tests for Australia.

"Billy has been absolutely tremendous for the Storm since his comeback and was instrumental in Queensland's success and that's why he's got the No.1 jersey," Meninga told SEN radio.

"There's a lot of competition at fullback with Darius Boyd, Josh Dugan and James Tedesco but Billy's got the inside running."

Meninga will name a 24-man World Cup squad in October and said players whose teams were in finals contention would have an advantage.

"If your clubs are playing finals and doing well that has a pretty strong impact on the final team because you're playing at the back end of the year," Meninga said.

"You're fit, healthy, able to stand up in big games, your confidence is high."

Meninga also made mention of Storm five-eighth Cameron Munster, who he said had an "outstanding" State of Origin debut for Queensland.

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