- Source: Gareth Williams (rugby union, born 1954)
Gareth Powell Williams (6 November 1954 – 12 May 2018) was a Wales international rugby union player who played club rugby for Bridgend RFC. In 1980, he toured South Africa with the British Lions as a replacement for the injured Stuart Lane.
He had suffered with multiple system atrophy since 2012 and had been bed-bound since 2017. He died in May 2018.
He was the brother of Owain Williams.