Andre AgassiAg·as·si, An·dre /ˈæɡəsi, ˈɒndreɪ $ ˈɑːn-/ (1970–) a former American tennis player who is one of the few players to have won all four major tennis tournaments: the Australian Open , the French Open, Wimbledon, and the US Open). He is married to the former tennis player Steffi Graf.