The Welshman was a product of the Crystal Palace Academy, with his development at the club beginning aged eight. He made his debut at the start of the 2011/12 season, though his breakthrough came in 2012/13.
After recovering from an injury that kept him out for more than half his debut season, Williams went on to make 35 appearances in the 12/13 campaign.
Williams was a feature for both Dougie Freedman and Ian Holloway during the promotion push and his efforts were rewarded as he claimed the Young Player of the Season award for 2012/13.
His efforts in red and blue and his longstanding affiliation to the club made him a cult hero amongst fans, earning the nickname ‘Joniesta.’
Williams’ career at Palace saw him go out on loan numerous times for the likes of Ipswich Town, Nottingham Forest, Milton Keynes Dons and Sunderland.
His time with the club came to a close in January 2019 as he made a move to Charlton Athletic. He then joined Cardiff City in February 2021.
Williams has also featured in the Wales national team throughout his career, including helping them on their way to the semi-finals of the 2016 European Championship.
In When Eagles Dare, we gain unprecedented insight into Williams' time at the club and how his breakthrough season played out during each of the five gripping episodes. Click here to get more info and watch When Eagles Dare.