The Neath-Swansea lock, a former Wales captain, replaced injuredCeltic Warriors second-row Brent Cockbain during last Saturday's 31-21defeat against world champions England at Twickenham.
Llewellyn, 35, now moves into the starting line-up after Cockbainfailed to recover from an ankle sprain.
Departing Wales coach Steve Hansen, paying tribute to Llewellyn,said: "Gareth is one of the senior players in our squad and isexpected to be a leader both on and off the field.
"He has done this with increasing success over the last twoyears, he is someone who has been a great asset to his country and will continueto do so long after chooses to retire, as I believe he will make a very goodcoach.
"He has looked after himself through the years and has been avaluable source of experience to the youngsters in the squad, as well asmaking his own contributions through his performances."
Llewellyn, who made his Test debut against New Zealand back in1989 and has scored five tries for Wales, is not the only change to the team thattook the field at Twickenham.
Back-rowJonathan Thomas, who sustained thigh and shoulderinjuries has been replaced by Cardiff's Martyn Williams.
Wales captain Colin Charvis switches to blindside flanker toaccommodate Williams on the open side.
In the backs Iestyn Harris and Tom Shanklin have been bracketedtogether at inside centre. Harris withdrew on the morning of the England gamebecause of a
Hansen, commenting on his midfield dilemma, said: "We willmake a decision on who will fill the No 12 shirt later in the week. Whoever missesout will be unlucky as they have both been in good form."
On the bench Celtic Warriors lock Robert Sidoli takes Llewellynsplace with Leeds back-row Alix Popham filling the gap vacated byWilliams.
Saturday's match will be Hansen's final game in charge of Walesbefore he returns to his native New Zealand to become a member of Walespredecessor turned All Black coach Graham Henry's staff. His two years in charge have left him with a Six Nations record ofjust two wins from 13 games. But this season both Wales and Italy have beaten Scotland, theonly team in the tournament who have lost all four of their matches so far.
Wales: Gareth Thomas (Celtic Warriors); Rhys Williams (Cardiff), MarkTaylor (Llanelli), Iestyn Harris (Cardiff) or Tom Shanklin (Cardiff), ShaneWilliams (Neath-Swansea); Stephen Jones (Llanelli), Gareth Cooper (CelticWarriors); Dafydd Jones (Llanelli), Martyn Williams (Cardiff), Colin Charvis, capt (Tarbes ); Michael Owen (Dragons), Gareth Llewellyn (Neath-Swansea);Gethin Jenkins (Llanelli), Robin McBryde (Llanelli), Duncan Jones(Neath-Swansea). Replacements: Mefin Davies (Celtic Warriors), Ben Evans (Cardiff),Robert Sidoli (Celtic Warriors,), Alix Popham (Leeds), Dwayne Peel(Llanelli), Ceri Sweeney (Celtic Warriors), Iestyn Harris (Cardiff) or TomShanklin (Cardiff)
AFP - 2004.