Having been in impressive form for the Ospreys, Biggar will be eager to put an end to Wales’ seven-match losing streak, having last started in the home defeat to Samoa in November.
Uncapped second row Andrew Coombs, from the Dragons, also gets the nod from interim head coach Rob Howley, stepping up in the absence of injured trio Bradley Davies, Luke Charteris and Alun Wyn Jones.
There was some good news however for Howley with Ian Evans fit to start alongside Coombs.
Adam Jones returns from injury in the front row, lining up alongside British and Irish Lions colleagues Gethin Jenkins and Matthew Rees.
Howley has also stuck with the three-quarter line that helped Wales to the Grand Slam last year, Jamie Roberts and Jonathan Davies in the centres and Leigh Halfpenny, George North and Alex Cuthbert making up the back three.
Sam Warburton will lead the team in an unchanged back row alongside Toby Faletau and Aaron Shingler.
On the bench, Harlequins second row Olly Kohn could make his international debut, but exciting youngster Eli Walker misses out due to injury.
And despite coming into the game on the back of a difficult recent run, Howley insists the Grand Slam champions are in good spirits.
“As a squad we have worked hard over the past two weeks and go into Saturday excited and confident at defending our title,” said Howley.
“It’s a boost to have Adam and Ian return from injury and it’s a great opportunity for Andrew who has been performing well at regional level to show what he can do on this stage.
“The Six Nations is all about momentum and we know we have to hit the ground running against Ireland.”
© Sportsbeat 2012
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