Williams was one of the first players to sign for the newly formed Cardiff Blues in the summer of 2003, having previously played for UWIC, Bridgend and Pontypridd and also the Sydney club, Gordon. He made two appearances for Wales A in 2001-02 before winning his Wales cap in the 2003 Six Nations' fixture in Italy.
An industrious Hooker, Gareth's career at the Cardiff Blues includes 26 Heineken Cup matches. He made his debut for the Blues in October of 2003 against Edinburgh and went on to make 14 appearances for the Blues in his first season.
The match against Leinster also sees the return of three Cardiff Blues players from injury. Xavier Rush, Jamie Roberts and Richie Rees are all on the bench for the Blues in their first match of 2009.
Rush, sustained an injury to his knee during summer training which required an operation. Despite having some game time against Connacht in late September he has not played since that match with the knee injury having not fully recovered until now.
Richie Rees, injured his shoulder playing against Glasgow in late November but is now fit to take a place on the bench. Jamie Roberts is also back having recovered from a fractured skull playing for Wales against Australia also in late November.
Cardiff Blues
15 Leigh Halfpenny
14 Tom James
13 Jamie Robinson
12 Tom Shanklin
11 Gareth Thomas
10 Nick Robinson
9 Jason Spice
8 Andy Powell
7 Robin Sowden Taylor
6 Maama Molitika
5 Paul Tito
4 Bradley Davies
3 Taufa'au Filise
2 T Rhys Thomas
1 John Yapp
16 Gethin Jenkins
17 Gareth Williams
18 Scott Morgan
19 Xavier Rush
20 Richie Rees
21 Ceri Sweeney
22 Jamie Roberts
Cardiff Blues All Time Top 10 Appearances
Nick Robinson 112
Deiniol Jones 111
T.Rhys Thomas 108
John Yapp 103
Gareth Williams 99
Jamie Robinson 98
Robin Sowden-Taylor 94
Martyn Williams 91
Nick Macleod 82
Gethin Jenkins 79
Guinness PRO12
Suite 208, Alexandra House,
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Ballsbridge, Dublin 4, Ireland