Wales have made nine changes to the team that narrowly lost to South Africa ahead of their clash with Fiji at the Millennium Stadium on Friday.
Ryan Jones returns to the starting line-up and regains the captaincy.
Ospreys fly-half Dan Biggar is part of a completely new half-back pairing and will be joined by the Blues’ Richie Rees, Stephen Jones and Mike Philips both take up a position on the bench.
Dragons wing Aled Brew starts in place of the injured Shane Williams (shoulder) and wins his fourth cap after last featuring on the international stage against England at Twickenham in 2007.
Ospreys centre Andrew Bishop is reunited with his regional colleague James Hook.
Up front it's an all Ospreys front row with Huw Bennett taking up hooker duties from Scarlet Matthew Rees, who is rested. In the second row Ian Gough (Ospreys) and Deiniol Jones (Blues) lock the scrum, with Bradley Davies (Blues) moving to the bench.
In the back row Jonathan Thomas is retained alongside returning captain and fellow Osprey Jones, Dragons back row Lydiate faces a fitness race to replace veteran Blues flanker Martyn Williams. If Lydiate returns from ankle trouble in time Williams will sit out the Fiji match, but should the Dragon fail fitness testing this week Williams will win his 98th cap for Wales.
On the bench Tongan born 'Toby' Faletau (full name: Tangaki Taulupe Faletau) is set to be Wales' 1079th player and 63rd teenager, following 18 year old Scarlets wing George North – who is retained on the right wing against Fiji – who made his double try-scoring debut last week.
"We must maintain our focus this week, if we even cast an eye beyond Fiji on Friday night, to the World Cup or even just to the game a week later we could be left counting the cost," said Wales head coach Warren Gatland.
"We know all too well that the Fijians bring an extra dimension to their game when they face Wales and there is no doubt they will have targeted us this weekend as a game think they can win.
"A couple of players, like Richie Rees and Huw Bennett get their chance to show what they can do from the start of a game rather than off the bench.
"And on the bench too we have a wealth of experience to call upon, should we need it, alongside a young man originally from Tonga who now qualifies for Wales who, at just 19, is already quite a prospect.
WALES: Lee Byrne; George North, James Hook, Andrew Bishop, Aled Brew; Dan Biggar, Richie Rees; Paul James, Huw Bennett, Adam Jones, Ian Gough, Deiniol Jones, Ryan Jones (captain), Dan Lydiate/Martyn Williams, Jonathan Thomas
REPLACEMENTS: Richard Hibbard, John Yapp, Bradley Davies, Toby Faletau, Mike Phillips, Stephen Jones, Tom Shanklin.