The 31-year-old, who scored six tries during the 2008 Six Nations to break the Wales all-time try scoring record, is the first Welshman to pick up the most prestigious individual award on the Rugby calendar.
Williams fought off stiff competition from New Zealand fly half and 2005 IRB Player of the Year Dan Carter, his Wales teammate Ryan Jones, Scotland scrum half Mike Blair and Italy captain Sergio Parisse to win the nomination from the IRB Awards judging panel convened by double Rugby World Cup winner John Eales.
"It's quite mad to be honest," said Williams moments after receiving the award. "It's been a hell of a year and this has just capped it off really. It's the biggest honour you can get as an individual in rugby and it's totally overwhelming."
Williams is the first player from the Northern Hemisphere to win the prestigious award since England's Johnny Wilkinson in 2003.
The International Rugby Players Association (IRPA) Try of the Year was awarded to the Irish team and Leinster's Brian O'Driscoll who scored a wonderful try against Australia in June.
Courtesy IRB.
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