Rosewall wins at age 38
In 1953, 18-year-old Ken Rosewall became the youngest Australian Open champion. In 1972, 37-year-old Rosewall became the oldest Australian Open champion. He defeated Malcolm Anderson 7-6 (2), 6-3, 7-5 in an all-Aussie final. It was Rosewall's eighth and final Grand Slam title, though he did reach the Wimbledon final in 1974, a few months shy of 40.