Six-time Wimbledon champion Roger Federer shrugged off a rare medical time-out to defeat Xavier Malisse 7-6 (7/1), 6-1, 4-6, 6-3 on Monday to reach a 33rd successive Grand Slam quarter-final. The Swiss great goes on to face either Russian 26th seed Mikhail Youzhny or Denis Istomin of Uzbekistan for a place in the semi-finals.