 Cockerell won gold at the World Junior Championships in the event's inaugural year, 1976.After moving up to the senior level, he won silver at three international competitions – the 1978 Nebelhorn Trophy in West Germany, 1978 Grand Prix International St. Gervais in France, and 1980 Ennia Challenge Cup in the Netherlands.Cockerell won his first senior national medal, bronze, at the 1983 U.S. Championships.