Andriy Medvedev was the defending champion but lost in the quarterfinals to Marc Rosset.
Roger Federer's first tournament as a professional was Gstaad in 1998, where he faced Lucas Arnold Ker in the round of 32 and lost, 4–6, 4–6.
 Federer's first final came at the Marseille Open, which was in 2000, and he lost to fellow Swiss Marc Rosset, 6–2, 3–6, 6–7.
 Federer's first win was at the 2001 Milan Indoor tournament, where he defeated Julien Boutter, 6–4, 6–7, 6–4.
 The most prestigious event finals he was in at this time was the Miami Masters event, where he lost to Andre Agassi, 3–6, 3–6, 6–3, 4–6.
 In addition, Federer won his first Master Series event at the Hamburg Masters on clay, 6–1, 6–3, 6–4, over Marat Safin.
 Federer made ten singles finals between 1998 and 2002, of which he won four and lost six.
 Federer made six doubles finals during this time, but lost the Indian Wells Masters event in 2002.
 The most prestigious events he won were the Hamburg Masters in 2002 and two Rotterdam 500 series events in 2001 and 2002.
Costa began playing tennis at the age of five.
 He first came to the tennis world's attention as an outstanding junior player.
 In 1993, he reached the French Open junior final and won the Orange Bowl.
 He turned professional later that year and quickly established a reputation as a strong clay court player.
 Spanish former player and commentator for Spanish television Andrés Gimeno used to call him "the man with two forehands", because he could hit with the same accuracy and strength both forehand and backhand.
 In 1994, he won two challenger series events and was named the ATP's Newcomer of the Year.
Marc Rosset was the defending champion, but lost in the first round this year.
Marc Rosset was the defending champion but lost in the second round to Julien Boutter.
Marc Rosset was the defending champion, but lost in the first round this year.
Marc Rosset (born 7 November 1970) is a former professional tennis player from Switzerland who is best remembered for winning the men's singles gold medal at the 1992 Olympic Games.
 He also won one Grand Slam doubles title at the French Open in 1992 partnering compatriot Jakob Hlasek.
Jakob Hlasek and Marc Rosset were the defending champions, but Rosset did not participate this year.
 Hlasek partnered Michiel Schapers, losing in the first round.
Marc Rosset was the defending champion at the Milan Indoor tennis tournament but lost in the second round to Greg Rusedski.
Marc Rosset was the defending champion, but lost in the second round to Renzo Furlan.

Question: Albert Costa and Marc Rosset were professional players in which sport?
Answer: tennis