Williams is a product of the Munster Rugby Academy. He plays his club rugby for Cork Constitution and is a former Schools and Ireland U21 international. Williams was on a development contract until awarded a full contract at the start of the 2010/11 season.
He signed a two-year contract extension with Munster in March 2012 and signed a one-year contract extension at the end of February 2014.
Duncan made his first European start away to Saracens in Round 5 of the Champions Cup in January 2015, and then signed a two-year contract extension with the province.
Williams earned his 150th cap for Munster on 10 February 2018, doing so when he started in the provinces' 33–5 win against Zebre in the 2017–18 Pro14.
Facial injuries suffered during training initially ruled Williams out for the remainder of the 2017–18 season, as surgery was required.
Williams heads into the 2018/19 season with 153 appearances for Munster and 35 points scored.
As of the 2018/2019 Champions Cup, Williams has had 21 European Cups appearances scoring 1 try and 5 points.
(LS August 2018)
ML 7/10/18
Career
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Cork Constitution Scrum Half |
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Munster Rugby Scrum Half |
2009 - 2018 |
