 Morison started his career at Northampton Town at the age of 16, progressing through the club's centre of excellence.After featuring regularly for the club's reserve team, Morison made his first-team debut in 2002, and played a total of 28 times for the club during his three years with Northampton.He left Northampton and joined Conference South side Bishop's Stortford for an undisclosed fee in November 2004.