Andre Agassi won 8 Grand Slam singles titles and is one of only a handful of men to complete the career Grand Slam, winning all four majors at least once. After a mid-1990s ranking slump that took him outside the top 100, he rebuilt his game under coach Brad Gilbert and returned to world No. 1 in his 30s, winning four of his eight majors from 2000 onward before retiring following the 2006 US Open — the reason he is classed here as post-2000.