On 13 November 2012, Williams confirmed he would be returning to rugby league after signing a one-year deal with the Sydney Roosters for the 2013 NRL season. His return was undertaken to honour a handshake agreement with Roosters chairman Nick Politis. It took over a month before his contract was officially approved and registered by the ARLC; he was "frogmarched into League Central to be grilled as part of the probe" into his contract. Williams's return coincided with the banning of the shoulder charge, a manoeuvre of which he has been described as the best and most famous exponent.