Pete Sampras and Andre Agassi are retired professional men's tennis players who were both ranked World No. 1 during the 1990s, Sampras holding the world's top-rank spot for a then-record 286 weeks while Agassi held it for 101 weeks. With contrasting styles and temperaments, they played each other 34 times from 1989 through 2002, with Sampras winning 20 matches. It has been named as one of the greatest tennis rivalries of all time.
In Grand Slam tournaments, they played in five finals, with Sampras winning four. They met for the first time in a Grand Slam final at the 1990 US Open, with Agassi the favorite because of his top-three ranking even though Sampras had defeated former World No. 1 players Ivan Lendl and John McEnroe on the way to the final. Sampras defeated Agassi in straight sets.
The next time the pair met at a Grand Slam final was at the 1995 Australian Open. Agassi beat Sampras in four sets.
In one of their matches, played in the 2001 US Open quarter-final, Sampras won with the score of 6–7(7), 7–6(2), 7–6(2), 7–6(5); throughout the match, no player managed to break the other's serve. The last match in their rivalry came at the 2002 US Open final. It was their first meeting in the final since Sampras won in 1995. Sampras went on to win the match in four sets. This was Sampras's last career match, he announced his retirement from the game a year later at the 2003 US Open. Agassi retired in 2006 after 20 years on the tour.
From their first ATP match to their 1995 US Open final match, their head-to-head was tied 8–8. From their 1995 US Open final match to 1999, their head-to-head was 9–3 in favor of Sampras. Agassi has often said that the 1995 US Open loss was a powerful blow to him that took him years to recover from; amid this and other psychological issues he subsequently plummeted to World No. 141, and it marked a significant shift in their rivalry. From 2000 to their last match in 2002, their head-to-head was tied at 3–3.
At the time of their retirements, Sampras held the all-time record for most men's Grand Slam titles, with 14. This broke Björn Borg's record of 11 titles won in the Open Era, as well as the 12 held then by Roy Emerson, predating the Open Era. Roger Federer has since overtaken Sampras with 18 titles. On the other hand, Agassi, who claimed 8 Grand Slam titles, was ranked joint third for most titles in the Open Era, and joint fifth all-time at the time of his retirement. Agassi was the second man after Rod Laver to win the singles Career Grand Slam in the Open Era and one of five (currently seven) overall. Having won the gold medal in men's singles at the 1996 Olympics, he is the first of only two male players to achieve a Career Golden Slam in singles tennis, the second being Rafael Nadal. The Career Grand Slam proved elusive for Sampras, as he was unable to find significant success on the serve-neutralizing clay courts, reaching only one French Open semi-final in his career. Agassi also held the record for most ATP Masters Series (AMS) shields (since 1990) with 17 (Nadal, Novak Djokovic and Federer have since overtaken him), and has been called the best service returner in the history of the game. In retirement, Agassi and Sampras have found bonds to continue their friendship on a deeper level.