After he became Champion in 1978, he defended the championship against
several challengers until he was defeated by Terry Stacey in 1985. He failed
to regain it in his challenge against Stacey in 1986. In 1987 Stacey lost the
championship to Piers Shepperson. In 1988 Macfadyen regained the title by defeating
Shepperson. He then again defended he championship against several challengers until
1993, when he was defeated by Shutai Zhang, who had trained in China as a professional
Go player. Macfadyen failed to regain the title from Zhang the next three years. In 1997
Zhang returned to his native China, and Macfadyen was then able once more to regain the
title. He has successfully defended it since then, losing only two games in the subsequent
eight championship matches.