Harrison started his basketball career at the late age of 16. With a short introduction to the game at Woking Blackhawks he then moved to Reading Rockets and worked his way to the mens team in Division 1 of the EBL. Harrison played four seasons with the Reading Rockets between 2008-2012.
In that time he worked his way through the ranks to secure a starting spot on the club’s Division One Men’s team. In his time with the Rockets, Harrison developed his skills which enabled him to play different positions as well as be a tough match up for any team. His ability to shoot the ball, score inside, and defend a variety of players helped the club win a substantial amount of silverware over the four seasons he played for the Rockets.
Harrison secured his first professional contract in August 2012 ready to start the basketball season in the Spanish European Basketball League (EBA) for CB Sant Josep Girona.
Since then Harrison has gone on to become the Riders current longest serving player play 5 seasons with the club winning 3 BBL Championships, 2 BBL Playoffs, 1 BBL cup and 3 BBL Trophies. Harrison had his best statistical season for the Riders in the 2017/18 campaign averaging 4.52 points, 1.87 rebounds and 0.96 assists a game.