Jason Knight was born on 13 February 2001 and grew up in Dublin, Ireland, where he was educated at Clonkeen College in Deansgrange. He began playing football at age four with Cabinteely before being signed by Derby County at sixteen, marking the start of a professional journey that would shape him into one of the more reliable midfielders in the EFL.
Knight made his Derby first-team debut in August 2019 and quickly established himself as a consistent performer, making 35 appearances and scoring six goals in his debut season. He was handed the club captaincy in January 2021 under Wayne Rooney — a notable honour for a player still in his teens. He went on to make over 150 appearances for Derby across all competitions, remaining loyal to the club even through administration and a 21-point deduction that resulted in relegation.
A energetic, box-to-box midfielder, Knight presses effectively and contributes at both ends of the pitch. He joined Bristol City on a four-year deal in July 2023 and was voted the club's Player of the Month for August in his debut season, underlining the immediate impact he made.
Knight has represented the Republic of Ireland at senior level since his debut against Finland in October 2020, also scoring his first international goal in a 4–1 friendly win over Andorra in June 2021. He has been capped at every age-group level from under-15 upwards.