of the sport's premier competitors was over and he would never again win any significant championships. 1998–2003: Return to glory and Career Super Slam In 1998, Agassi began a rigorous conditioning program and worked his way back up the rankings by playing in Challenger Series tournaments, a circuit for pro players ranked outside the world's top 50. After returning to top physical and mental shape, Agassi recorded the most successful period of his tennis career and also played classic matches in that period against Pete Sampras and Patrick Rafter. In 1998, Agassi won five titles and leapt from No. 110 to No. 6, the highest jump into the top 10 made by any player during a calendar year. At Wimbledon, he had an early loss in the second round to Tommy Haas. He won five titles in ten finals and was runner-up at the Masters Series tournament in Key Biscayne, losing to Marcelo Ríos, who became No. 1 as a result. At the year end he was awarded the ATP Most Improved Player of the Year for the second time in his career (the first being 10 years earlier in 1988). Agassi entered the history books in 1999 when he came back from two sets to love down to beat Andrei Medvedev in a five-set French Open final, becoming, at the time, only the fifth male player (joining Rod Laver, Fred Perry, Roy Emerson and Don Budge—these have since been joined by Roger Federer, Rafael Nadal, and Novak Djokovic) to win all four Grand Slam singles titles during his career. Only Laver, Agassi, Federer, Nadal and Djokovic have achieved this feat during the Open Era. This win also made him the first (of only four, the next being Federer, Nadal and Djokovic respectively) male player in history to have won all four Grand Slam titles on three different surfaces (clay, grass and hard courts). Agassi also became the only male player to win the Career Super Slam, consisting of all four Grand Slam tournaments plus an Olympic gold medal in singles and a Year-end championship. Agassi followed his 1999 French Open victory by reaching the Wimbledon final, where he lost to Sampras in straight sets. He rebounded from his Wimbledon defeat by winning the US Open, beating Todd Martin in five sets (rallying from a two sets to one deficit) in the final. Overall during the year Agassi won 5