 Federer entered the top 100 ranking for the first time on 20 September 1999 . His first final came at the Marseille Open in 2000 , where he lost to fellow Swiss Marc Rosset . Federer won the 2001 Hopman Cup representing Switzerland , along with Martina Hingis . The duo defeated the American pair of Monica Seles and Jan @-@ Michael Gambill in the finals . Federer 's first singles win was at the 2001 Milan Indoor tournament , where he defeated Julien Boutter in the final . Although he won his first title already in 1999 on the Challenger tour , winning the doubles event in Segovia , Spain with Dutchman Sander Groen , the final was played on Federer 's 18th birthday . In 2001 , Federer made his first Grand Slam quarterfinal at the French Open , and at Wimbledon that same year defeated four @-@ time defending champion Pete Sampras to reach the quarterfinals . The most prestigious event final he reached during this period was the 2002 Miami Masters event , where he lost to Andre Agassi on hard court . 
