Stephen Jones (Scarlets) and Ryan Jones (Ospreys), both British and Irish Lions veterans and double Six Nations Grand Slam winners, make their returns from calf problems to feature for the first time in the 2011 tournament, replacing Rhys Priestland (Scarlets) and the injured Dragon Dan Lydiate (ankle) respectively.
Scarlets fly-half Jones will be appearing in his fourth RWC and is set to break Wales' all-time appearance record by winning his 101st cap, one more than 2007 RWC captain Gareth Thomas (Jones also has six Lions caps).
Ospreys back row Jones, one of four players in the squad who share that surname, adds 53 and makes his RWC debut after injury prevented his selection in 07.
The third senior player to return is Blues prop Gethin Jenkins, who adds his 77 caps to the experience tally, moving from the bench to replace Osprey Paul James.
Another former Lion, Clermont full-back Lee Byrne joins Dragons wing Aled Brew and Exeter prop Craig Mitchell, alongside the two Joneses, to make it a total of five players making their first appearances of this RWC campaign.
Byrne replaces James Hook (Perpignan), who has a shoulder problem, and Brew and Mitchell replace Shane Williams and Adam Jones (both Ospreys), who miss out altogether.
Promoted from bench duty to the forward pack alongside Jenkins are Dragons hooker Lloyd Burns, replacing Osprey Huw Bennett, and Blues lock Bradley Davies, replacing Luke Charteris.
Dragons second row specialist Charteris moves to the bench and is joined by uncapped Scarlets hooker Ken Owens, and Ospreys prop Ryan Bevington, with Bennett omitted.
It's all change in the backs with only Scarlets centre Jonathan Davies retained to be partnered with his Regional team-mate Scott Williams, who didn't appear from the bench last weekend, but whose presence in the Welsh midfield means Blues stalwart Jamie Roberts misses out on this occasion.
Blues wing Leigh Halfpenny, who came on at full-back against Samoa for the injured Hook, replaces George North on the wing, with the Scarlets' 19-year-old flier retained in the 22 to provide cover.
Tavis Knoyle takes up the mantle at scrum-half, also re-uniting a Regional partnership with fellow Scarlet Jones and replacing Mike Phillips.
Phillips is also omitted from the 22 with Blues scrum-half Lloyd Williams handed the chance to add to the cap he won at the Millennium Stadium this summer in Wales' RWC warm-up victory over Argentina.
"On the back of two tough and intensely physical matches we have been able to make some changes to the squad, but also bring a lot of experience into the side at the same time," said Wales coach Warren Gatland.
"Stephen, Ryan and Gethin in particular bring a wealth of experience but we have some previously established combinations elsewhere in the side as well, in the second row, the midfield and at halfback, so we are excited and looking for this side to do well against Namibia.
"They will be hurting after their loss to South Africa, but we will be concentrating on ourselves and our own performance.
"This is the Rugby World Cup and every performance counts, we showed great heart and courage last week to grind out a win and this week we need to do similar, but also improve and take that next step towards qualification from this incredibly tough group."
WALES: Lee Byrne; Leigh Halfpenny, Jonathan Davies, Scott Williams, Aled Brew; Stephen Jones, Tavis Knoyle; Gethin Jenkins, Lloyd Burns, Craig Mitchell, Bradley Davies, Alun Wyn Jones, Ryan Jones, Sam Warburton (C), Toby Faletau
REPLACEMENTS: Ken Owens, Ryan Bevington, Luke Charteris, Andy Powell, Lloyd Williams, Rhys Preistland, George North