Stephen Jones is out of the Wales side to face England in the Lloyds TSB Six Nations match at Twickenham.
The Llanelli outside half has not recovered from the back spasms he suffered during the week and Iestyn Harris will take his place.
It will be the first time Harris has started a Lloyds TSB Six Nations match in his club position and he will be joined at half-back by his Cardiff partner Rob Howley.
Harris figured at centre in the opening championship match against Ireland and came on as a second half replacement full back against Italy.
Another Cardiff player, Nicky Robinson, has been brought onto the replacements bench to fill Harris' shirt. He was due to play for Wales Under 21 against England Under 21.
England have also had to make a change to their replacements. Sale Sharks outside half Charlie Hodgson has withdrawn through injury and Bath's Iain Balshaw has taken his place.
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.