I thought that it would be interesting to compile a list of players that have beaten ATP number 1 players multiple times (while they were ranked number 1) at the grand slam tournaments only. Nadal d. Federer FO 2007 Nadal d. Federer FO 2006 Nadal d. Federer FO 2005 Safin d. Federer AO 2005 Safin d. Roddick AO 2004 Philippoussis d. Agassi W 2003 Philippoussis d. Sampras AO 1996 Agassi d. Hewitt USO 2002 Agassi d. Sampras AO 1995 Kafelnikov d. Kuerten USO 2001 Kafelnikov d. Sampras FO 1996 Kafelnikov d. Agassi FO 1995 Sampras d. Agassi USO 1995 Sampras d. Courier USO 1992 Rafter d. Agassi W 2000 Rafter d. Sampras USO 1998 Courier d. Sampras FO 1994 Courier d. Edberg FO 1991 Becker d. Agassi W 1995 Becker d. Lendl W 1989 Becker d. Lendl USO 1989 Becker d. Lendl W 1988 Becker d. Lendl W 1986 Edberg d. Lendl W 1990 Edberg d. Lendl AO 1985 Wilander d. Lendl USO 1988 Wilander d. McEnroe FO 1985 Cash d. Lendl AO 1988 Cash d. Lendl W 1987 Cash d. Lendl AO 1987 Firstly I must admit that I was using ATP data for these players and the rankings were incomplete at times and non-existant before 1985. Secondly I was suprised (even given the limmits of the data) how few players had beaten two or more ATP number 1s at the grand slam tournaments. Feel free to add to my list or comment on it. It would be great if someone had some of the rankings data from earlier in the open-era.