Rafter won the Australian Open men's doubles title in 1999 (partnering Jonas Björkman), making him one of few players in the modern era to win both a singles and doubles Grand Slam title during their career (fellow countryman Lleyton Hewitt would later achieve this feat in 2001). He and Björkman also won a doubles titles at the ATP Masters Series event in Canada (1999) At the 1999 French Open, Rafter drew future world No. 1 and 20-time Grand Slam champion Roger Federer in the first round, making him the first-ever opponent of Federer in the main draw of a Grand Slam tournament. Rafter defeated him in four sets. Rafter then reached the Wimbledon semifinals for the first time in 1999, losing in straight sets to Agassi. This was the first of three consecutive years that the two met in the Wimbledon semifinals. July 1999 saw Rafter holding the world No. 1 men's singles ranking for one week, making him the shortest-reigning world No. 1 in ATP Tour history. As the two-time defending US Open champion, Rafter lost in the first round of the tournament, retiring in the fifth set against Cédric Pioline after succumbing to shoulder tendinitis. Rafter's shoulder injury wound up being serious enough to necessitate surgery.