Former Wallabies hooker Brendan Cannon believes the battle for the Wallabies No.2 jersey is wide open ahead of the 2019 Rugby World Cup. Following Stephen Moore’s retirement overnight and Tatafu Polota-Nau’s decision to sign a two and a half year deal with UK club Leicester, Wallabies coach Michael Cheika will need to fill a number of spots in his training squad in 2018. “Tatafu heading overseas for a stint will probably be a really good thing because we’ll have four young starting hookers playing Super Rugby next year, plus the reserves adding depth and I think it’s going to be fantastic over the next 18-24 months to watch how they all grow,” Cannon told Rugby News. “Cheika has blooded a heap of young blokes over the last year or so and that’s exactly what you need to do this far out from the World Cup.” While 78-cap veteran Polota-Nau will still be eligible to play for the Wallabies, the hooker will be 34 by the start of the 2019 World Cup and will need