From West Heidelberg, Watt was a classy left footer who made his debut with the Magpies when only 16 years old. He had height, pace and sure ball handling skills, and many believed he would be groomed for a key position. In 1964 he suffered a back injury early in the year, but made it back for the finals and played in the losing Grand Final side. A succession of knee problems meant that it was 1967 before he was able to win a regular senior place again, and he had two excellent years, making the state side four times and winning All-Australian selection in 1968. He was 19th man in the 1970 side that lost the grand final and it was his last appearance for the club at the age of 23. He injured his Achilles and missed 1971 before attempting a partial comeback with VFA club Coburg. After that, he coached successfully in Tasmania, and later became a successful administrator at St Kilda.