Question: Angelique Kerber and Hana Mandlíková are both what?

full_context: Document 1: 2016 Australian Open – Women's Singles: Serena Williams was the defending champion, and attempting for the second time to equal Steffi Graf's career record of 22 major singles titles. She lost in the final to Angelique Kerber, 4–6, 6–3, 4–6. Kerber became the first woman to win a singles major title after having saved a match point in the first round, which she did against Misaki Doi. She is also the first German of either sex to win a major since Graf at the 1999 French Open.
Document 2: 1988 Australian Open – Women's Singles: Hana Mandlíková was the defending champion, but was defeated by Steffi Graf in the quarterfinals. Graf ended up winning the tournament, defeating Chris Evert in the final, 6–1, 7–6. This would be Chris Evert's 34 appearance in a Grand Slam final, an Open Era record, and her 6th final, Evert made the final in every Australian Open she played. This was the first Grand Slam Final played under a roof. There was an 1 hour and 23 minute delay to close the roof at 1-1 in the first set. This was Graf's first step towards completing the first and so far only calendar year Golden Slam.
Document 3: Li Na: Li Na (; ; born 26 February 1982) is a retired Chinese professional tennis player, who achieved a career-high WTA-ranking of world No. 2 on 17 February 2014. Over the course of her career, Li won seven WTA singles titles and two Grand Slam singles titles at the 2011 French Open and 2014 Australian Open. Li's rise to prominence came after those victories, which made her the first and only Grand Slam singles champion from East Asia and Asia as a whole. Prior to this, she had already become the first player representing an East Asian and Asian country to appear in a Grand Slam singles final, a milestone she achieved at the 2011 Australian Open. Li was also the runner-up at the 2013 Australian Open and 2013 WTA Tour Championships, a three-time quarterfinalist at Wimbledon and a semifinalist at the 2008 Beijing Olympic Games and 2013 US Open. Among her other most notable accolades, she was the first Chinese player to win a WTA tour title at the Guangzhou International Women's Open in 2004, the first to reach a Grand Slam singles quarterfinal at the 2006 Wimbledon Championships, and the first to break into the world's top 10. Her feats have sparked a major population growth of tennis players in East Asia, earning her the reputation as the region's tennis pioneer and trailblazer.
Document 4: Evert–Mandlikova rivalry: The tennis players Chris Evert (United States) and Hana Mandlíková (Czechoslovakia/Australia) met 26 times during their careers. Evert leads their overall head-to-head series 19–7. In 1981 the rivalry was described as being the most "dramatic" in women's tennis.
Document 5: 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 6: 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 7: 1988 Virginia Slims of Washington – Singles: Hana Mandlíková was the defending champion but lost in the semifinals to Martina Navratilova.
Document 8: Garbiñe Muguruza: Garbiñe Muguruza Blanco (] ; born 8 October 1993) is a Spanish-Venezuelan tennis player who is currently ranked world No. 1 in singles by the Women's Tennis Association (WTA). Since turning professional in 2012, she has won five singles titles, including two majors at the 2016 French Open and the 2017 Wimbledon Championships.
Document 9: Hana Mandlíková: Hana Mandlíková (born 19 February 1962) is a former professional tennis player from Czechoslovakia who later obtained Australian citizenship. During her career, she won four Grand Slam singles titles: the 1980 Australian Open, 1981 French Open, 1985 US Open, and the 1987 Australian Open. She was also the runner-up at four Grand Slam singles events, including the Wimbledon finals of 1981 and 1986, and won one Grand Slam women's doubles title, the 1989 US Open with Martina Navratilova.
Document 10: 2017 US Open – Women's Singles: Angelique Kerber was the defending champion, but lost in the first round to Naomi Osaka. This loss would cause Kerber to fall outside the top ten in the WTA rankings for the first time since 2015.
Document 11: 2016 Angelique Kerber tennis season: The 2016 Angelique Kerber tennis season officially began on 5 January with the start of the 2016 Brisbane International. Kerber entered the season as the number 10 ranked player and the defending champion at four tournaments.
Document 12: Martina Navratilova: Martina Navratilova (Czech: "Martina Navrátilová" ] ; born Martina Šubertová ] ; October 18, 1956) is a former Czechoslovak and later American tennis player and coach. In 2005, "Tennis" magazine selected her as the greatest female tennis player for the years 1965 through 2005 and she is considered one of the best, if not the best, female tennis players of all time.
Document 13: 1984 US Open – Women's Singles: Martina Navratilova was the defending champion, and she successfully defended her title, defeating last year's finalist Chris Evert in the final. This victory was Navratilova's sixth straight Major title, tying her with Margaret Court and Maureen Connolly for the most consecutive Grand Slam titles won. Navratilova became the first player to win Grand Slams on clay, grass and hard court on the same calendar year, after having won the French Open and Wimbledon.
Document 14: Angelique Kerber career statistics: This is a list of the main career statistics of German professional tennis player, Angelique Kerber. To date, Kerber has won ten WTA singles titles including two grand slam singles titles at the 2016 Australian Open and 2016 US Open and at least one title on each playing surface (hard, clay and grass). She was also the runner-up at the 2016 Wimbledon Championships and a Silver medalist at the 2016 Rio de Janeiro Olympics. Kerber became the world No. 1 for the first time in her career on 12 September 2016.
Document 15: Angelique Kerber: Angelique Kerber (] ; born 18 January 1988) is a German professional tennis player and former world No. 1. Having made her professional debut in 2003, Kerber rose to prominence upon reaching the semifinals of the 2011 US Open as the no. 92 ranked player in the world. She ascended to the top of the rankings on 12 September 2016, thus becoming the twenty-second and oldest player to achieve the number one ranking for the first time and the first new number one player since Victoria Azarenka in 2012.
ground_truth: tennis player