The 1980 Open Championship was the 109th Open Championship held from 17–20 July at Muirfield Golf Links in Gullane, Scotland. Tom Watson won his third Open Championship, four strokes ahead of runner-up Lee Trevino. It was the fourth of Watson's eight major titles; he won two additional Opens in 1982 and 1983. It was Watson's first win in a major in three years. This was the first Open scheduled to end on a Sunday, with a Thursday start. The Open previously began on Wednesday and ended on Saturday. Prior to 1966, the final two rounds were scheduled for Friday.