Question: Between two tennis players Kim Clijsters and Mary Pierce, who is older?

full_context: Document 1: Mary Joe Fernández: Mary Joe Fernández Godsick (born María José Fernández; August 19, 1971) is an American former professional tennis player. She reached a career-high ranking of world No. 4 in both singles and doubles. Fernández was the runner-up in three Grand Slam singles tournaments and won two Grand Slam women's doubles titles and two Olympic gold medals.
Document 2: Mary Pierce: Mary Pierce (born 15 January 1975) is a French retired tennis professional who played on the Women's Tennis Association (WTA) tour. Born in Canada, she is a citizen of Canada, and the United States. Pierce played for France in team competitions and in the Olympics.
Document 3: Jennifer Capriati: Jennifer Maria Capriati (born March 29, 1976) is an American former professional tennis player. A member of the International Tennis Hall of Fame, she won three singles championships in Grand Slam tournaments and a gold medal at the 1992 Summer Olympics in Barcelona, reached the World No. 1 ranking, and is considered one of the greatest tennis players of all time.
Document 4: Clijsters–Henin rivalry: Justine Henin and Kim Clijsters are Belgian professional tennis players who engaged in a long-standing rivalry which spanned twenty-five meetings over a twelve-year period, with eight taking place in a Grand Slam tournament. Their final competitive meeting came at the 2010 Wimbledon Championships in the fourth round, with Clijsters winning in 3 sets, this brought their head to head record to 13–12 in Clijsters' favour. The Belgians have met eight times in Grand Slam tournaments, three of which were finals. Henin leads 5–3 in Grand Slam play including winning all their final match-ups.
Document 5: Kim Clijsters: Kim Antonie Lode Clijsters (] ; born 8 June 1983) is a Belgian former professional tennis player. Clijsters is a former world No. 1 in both singles and doubles.
Document 6: Justine Henin: Justine Henin (] ; born 1 June 1982), known between 2002 and 2007 as Justine Hénin-Hardenne, is a Belgian former professional tennis player known for her all-court style of play and notably being one of the few female players to use a single-handed backhand. She spent a total of 117 weeks as the world No. 1 and was the year-end No. 1 in 2003, 2006 and 2007.
Document 7: Chris Evert: Christine Marie Evert (born December 21, 1954), known as Chris Evert Lloyd from 1979 to 1987, is a former World No. 1 professional tennis player from the United States. She won 18 Grand Slam singles championships and three doubles titles. She was the year-ending World No. 1 singles player in 1974, 1975, 1976, 1977, 1978, 1980, and 1981. Overall Evert won 157 singles championships and 32 doubles titles.
Document 8: Martina Hingis: Martina Hingis (born 30 September 1980) is a Swiss professional tennis player, a former world No. 1 singles player and currently ranked world No. 2 in doubles by the WTA. She has spent a total of 209 weeks as the singles No. 1 and has won five Grand Slam singles titles, thirteen Grand Slam women's doubles titles, winning a calendar-year doubles Grand Slam in 1998, and seven Grand Slam mixed doubles titles; for a combined total of twenty-five major titles. In addition, she has won the season-ending WTA Championships two times in singles and three times in doubles, and an Olympic silver medal.
Document 9: Marion Bartoli: Marion Bartoli (] ; born 2 October 1984) is a French former professional tennis player. She won the 2013 Wimbledon Championships singles title after previously being runner-up in 2007 and was a semifinalist at the 2011 French Open. She also won eight Women's Tennis Association singles titles and three doubles titles. She announced her immediate retirement from professional tennis on 14 August 2013.
Document 10: Mary Carillo: Mary Carillo (born March 15, 1957) is an American sportscaster and former professional tennis player. She is a reporter for NBC Sports and NBC Olympics.
Document 11: 1995 Peters International – Women's Doubles: Patty Fendick and Meredith McGrath were the defending champions but they competed with different partners that year, Fendick with Mary Joe Fernández and McGrath with Rennae Stubbs.
Document 12: Lindsay Davenport: Lindsay Ann Davenport Leach (born June 8, 1976) is an American former professional tennis player. She was ranked World No. 1 on eight different occasions, for a total of 98 weeks. Davenport is one of five women who have been the year-end World No. 1 at least four times (1998, 2001, 2004, and 2005) since 1975; the others are Chris Evert, Steffi Graf, Martina Navratilova and Serena Williams. She has achieved the No. 1 ranking in doubles as well.
Document 13: Sandrine Testud: Testud broke into top 20 singles rankings in July 1997. On February 7, 2000, she became the sixth Frenchwoman after Françoise Dürr, Mary Pierce, Nathalie Tauziat, Amélie Mauresmo and Julie Halard to break into the singles top 10 rankings. This marked the first time France had four women ranked in the singles Top 10 simultaneously (Mary Pierce at No. 5, Nathalie Tauziat at No. 6, Julie Halard at no.8 and Testud at No. 9). France was the third nation after the USA and Australia to have more than two representatives in the singles Top 10 at any one time. She finished in the top 20 singles rankings for five consecutive years between 1997 and 2001. In the summer of 2002, she took a break from the tennis circuit when she discovered that she was pregnant with her first child. She resumed her career 12 months after the birth of her child and retired in the summer of 2005.
Document 14: Serena Williams: Serena Jameka Williams (born September 26, 1981) is an American professional tennis player. The Women's Tennis Association (WTA) has ranked her world No. 1 in singles on eight occasions, from 2002 to 2017. She became the world No. 1 for the first time on July 8, 2002. On the sixth occasion, she held the ranking for 186 consecutive weeks, tying the record set by Steffi Graf for the most consecutive weeks as world No. 1 by a female tennis player. In total, she has been world No. 1 for 319 weeks, which ranks her third in the Open Era among female tennis players. Some commentators, players and sports writers regard her as the greatest female tennis player of all time.
Document 15: 2000 du Maurier Open – Women's Doubles: The 2000 du Maurier Open – Women's Doubles was the women's doubles event of the one hundred and eleventh edition of the Canadian Open; a WTA Tier I tournament and the most prestigious women's tennis tournament held in Canada. Jana Novotná and Mary Pierce were the defending champions, but Novotná retired from professional tennis in 1999 and Pierce did not compete at the tournament. Martina Hingis and Nathalie Tauziat won the title by defeating Julie Halard-Decugis and Ai Sugiyama 6–3, 3–6, 6–4 in the final. It was the 11th title for Hingis and the 21st title for Tauziat in their respective doubles careers.
ground_truth: Mary Pierce