Hook handed fly-half role
James Hook will make his second start at fly-half in this season's RBS 6 Nations Championship when Wales face Ireland on Saturday.
Hook, who wore the number 10 shirt and guided Wales to victory over Scotland at Murrayfield last month, replaces Stephen Jones.
Jones is on the bench, with fit-again Scarlets centre Jonathan Davies returning to midfield alongside Jamie Roberts after Hook deputised for him against Italy 10 days ago.
One other change from Rome sees a recall for Cardiff Blues wing Leigh Halfpenny, who is preferred to the unlucky Morgan Stoddart, a try-scorer against England and Italy.
Wales coach Warren Gatland has otherwise retained the team that triumphed at Stadio Flaminio, which means scrum-half Mike Phillips and number eight Ryan Jones both winning their 50th caps.
Despite Wales yesterday reporting a number of injury niggles, Gatland brought forward his team announcement by 48 hours to today.
He will choose two from three back-five forwards - Rob McCusker, Andy Powell and Jonathan Thomas - after fitness checks on Thursday, while there is a confirmed place among the substitutes for Sale scrum-half Dwayne Peel.
Gatland will break the Wales coaching record of 35 Tests in charge on Saturday, eclipsing Alan Davies' mark. Ireland though, have only lost once in Cardiff since 1983.
Gatland said: "This is a crucial game for us as a win will keep us in the Championship mix and take us into that final round with everything still to play for
"But it is also a big game for Ireland, who are in a similar position to us going into this match."
Addressing the fly-half issue, assistant coach Robin McBryde challenged Hook to justify the faith shown in him.
McBryde said: "The debate at fly-half will continue long after the Championship is over, but we have gone for James on this occasion.
"James provides a running threat and we will be looking for him to show he can control the game as well and help us play in the right areas."
Of Halfpenny's recall, McBryde added: "Leigh had a good run out for the Blues at the weekend, we know all about his pace and what he offers around the field as well as being solid under the high ball and giving us a long-range kicking option.
"Morgan misses out, but he has done nothing wrong and we know he can be relied on if we need him from the bench.
"We also have a vast amount of experience in Stephen (Jones) and Dwayne to call upon if necessary. Both have proved in the past that they can come on and make an impact and neither will let us down."