Question: How many Grand Slam singles titles did the tennis player, who defeated Hana Mandlíková, during the 1988 Australian Open – Women's Singles, win?

Context paragraphs:
Ken Rosewall: Kenneth Robert Rosewall {'1': ", '2': ", '3': 'AM, MBE', '4': "} (born 2 November 1934) is a former world top-ranking amateur and professional tennis player from Australia.  He won a record 23 tennis Majors including 8 Grand Slam singles titles and before the Open Era a record 15 Pro Slam titles and a record 35 Major finals overall.  He won the Pro Grand Slam in 1963.  Rosewall won 9 slams in doubles with a career double grand slam.  He is considered to be one of the greatest tennis players of all time.  He had a renowned backhand and enjoyed a long career at the highest levels from the early 1950s to the early 1970s.  Rosewall was one of the two best male players for about nine years and was the World No. 1 player for a number of years in the early 1960s.  He was ranked among the top 20 players, amateur or professional, every year from 1952 through 1977.  Rosewall is the only player to have simultaneously held Pro Grand Slam titles on three different surfaces (1962–1963).  At the 1971 Australian Open he became the first male player during the open era to win a Grand Slam tournament without dropping a set.

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.

2017 Australian Open – Men's singles final: The 2017 Australian Open Men's Singles final was the championship tennis match of the Men's Singles tournament at the 2017 Australian Open.  It was contested between Roger Federer and Rafael Nadal, ranked 17th and 9th in the world respectively.  It was their record ninth meeting in a Grand Slam final in their rivalry, and their 1st meeting in a Grand Slam final since the 2011 French Open.  In a rematch of the 2009 Australian Open final, which Nadal won in 5 sets, Roger Federer won the duel in 5 sets, beating Nadal for the first time in a Grand Slam since the 2007 Wimbledon final.  He also trailed Nadal 3–1 in the final set but won 5 games in a row to win the title.  This ended a 6-match losing streak against Nadal in Grand Slam events.  Having lost all of their previous three encounters, this was the first time Federer defeated Nadal at the Australian Open and also marked Federer's first Grand Slam victory over Nadal outside the grass courts of Wimbledon.  Federer extended his record of Grand Slam men's singles titles to 18, marking the third time he broke his own all-time record, after breaking the previous record of 14, held by Pete Sampras.

Petra Kvitová career statistics: This is a list of the main career statistics of Czech professional tennis player Petra Kvitová.  To date, Kvitová has won 20 singles titles including two Grand Slam singles titles at the Wimbledon Championships, one WTA Tour Championships singles title, two WTA Premier Mandatory singles titles and four WTA Premier 5 singles titles.  She was also the bronze medallist at the 2016 Rio Olympics, a semifinalist at the 2010 Wimbledon Championships, 2012 Australian Open and 2012 French Open and a quarterfinalist at the 2011 Australian Open, 2012 Wimbledon Championships, 2013 Wimbledon Championships, 2015 US Open and 2017 US Open.  Kvitová reached her career-high ranking of world no. 2 on 31 October 2011.

Jim Courier: James Spencer Courier Jr. (born August 17, 1970) is an American former World No. 1 professional tennis player.  During his career, he won four Grand Slam singles titles, two at the French Open and two at the Australian Open.  He holds the record for being the youngest man to have reached the finals of all four Grand Slam singles tournaments, at the age of 22 years and 11 months.  He also won five Masters 1000 series titles.  Until Novak Djokovic in 2016, Courier was the last man to win both the Australian and French Opens in the same calendar year.

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.

Anne Minter: Anne Minter (born 3 April 1963) is a former tennis player from Australia, who competed for her native country at the 1988 Summer Olympics in Seoul.  She was an Australian Institute of Sport scholarship holder.  She won four singles titles on the WTA Tour: 1987 Taipei, Singapore; 1988 Puerto Rico; 1989 Taipei.  Minter was a quarterfinalist at the Australian Open in 1988, beating fourth seed Pam Shriver in the R16 when the tournament moved to the hard court surface at Melbourne Park.  She twice reached the R16 at Wimbledon, upsetting ninth seed Hana Mandlíková in the third round in 1988.  She reached her highest individual ranking in her professional career on 4 July 1988, when she became the 23rd top player in the world.  On 19 March 1990 she reached her highest doubles ranking or 68.  Her playing career spanned 11 years from 1981 until 1992.  Minter's win-loss record for singles stands at 258–245.

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.

Williams sisters: The Williams sisters are two professional American tennis players: Venus Williams (b. 1980), a seven-time Grand Slam title winner (singles), and Serena Williams (b. 1981), twenty-three-time Grand Slam title winner (singles), both of whom were coached from an early age by their parents Richard Williams and Oracene Price.  There is a noted professional rivalry between them – between the 2001 US Open and the 2017 Australian Open tournaments, they met in nine Grand Slam singles finals.  They became the first two players, female or male, to play in 4 consecutive grand slam singles finals from the 2002 French Open to the 2003 Australian Open; Serena famously won all 4 to complete the first of two "Serena Slams".  Between 2000 and 2016, a 17-year span, they collectively won 12 Wimbledon singles titles (Venus won 5 and Serena won 7).  By winning the 2001 Australian Open women's doubles title, they became the 5th pair to complete the Career Doubles Grand Slam and the only pair to complete the Career Doubles Golden Slam.  At the time, Venus and Serena were only 20 and 19 years old, respectively.  Since then they have gone on to add another two Olympic gold medals in the 2008 Beijing Olympics and the 2012 London Olympics.  Nearly a decade later, the duo would go on to win 4 consecutive grand slam doubles titles from 2009 Wimbledon through 2010 Roland Garros, which would catapult them to co-No.  1 doubles players on 7 June 2010.  Two weeks later, on 21 June 2010, Serena would hold the No. 1 singles ranking and Venus would be right behind her at No. 2 in singles.  Their most recent grand slam doubles titles came at the 2012 Wimbledon & 2016 Wimbledon events.  They remain very close, often watching each other's matches in support, even after one of them has been knocked out of a tournament.

Steffi Graf: Stefanie Maria "Steffi" Graf (] ; born 14 June 1969) is a German former tennis player, who was ranked world No. 1 during her career.  Graf won 22 Grand Slam singles titles.  Her 22 singles titles put her second on the list of Major wins in the female competition since the introduction of the Open Era in 1968 and is third all-time behind Margaret Court (24) and Serena Williams (23).  In 1988, she became the first and only tennis player (male or female) to achieve the Golden Slam by winning all four Grand Slam singles titles and the Olympic gold medal in the same calendar year.  Furthermore, she is the only tennis player to have won each Grand Slam event at least four times.

Supporting paragraphs: 1988 Australian Open – Women's Singles Steffi Graf
Answer: 22