Question: Who won a Grand Slam singles title first, Thomas Muster or Goran Ivanišević?
Context: Brad Drewett (19 July 1958 – 3 May 2013) was an Australian tennis player and ATP official.  He was the 1975 and 1977 Australian Open Junior champion and the youngest player at age 17 to win the title since Ken Rosewall and John Newcombe.  He was also the third-youngest Australian Open quarter-finalist in his first Grand Slam, at 17 years 5 months in 1975, behind Boris Becker, 17 years 4 days in 1984 and Goran Ivanišević, 17 years 4 months in 1989. Sandra Reynolds Price ("née" Reynolds; born 4 March 1934) is a former tennis player from South Africa who won four Grand Slam women's doubles championships and one Grand Slam mixed doubles championship.  Her best Grand Slam singles result was reaching the 1960 Wimbledon final, losing to Maria Bueno 8–6, 6–0.  Reynolds is the only female player from South Africa to have reached the Wimbledon singles final, and she is one of three to have reached a singles final in a Grand Slam.  In 1961, she was seeded no. 1 for the Wimbledon Ladies Singles Championship, making her the only South African player (man or woman) ever to be seeded first in a Grand Slam singles event.  She was the runner-up at the 1959 , losing to Sally Moore in the final.  Price won the German Championships in 1960, 1961, and 1962.  She was the runner-up at the 1959 Italian Championships, having defeated Bueno in a semifinal, then losing to Christine Truman in the final. The 1997 Croatian Indoors was a men's tennis tournament played on indoor carpet courts at the Dom Sportova in Zagreb in Croatia and was part of the World Series of the 1997 ATP Tour.  It was the second edition of the tournament and took place from January 27 through February 2, 1997.  Goran Ivanišević won the singles title. Jelena Genčić (Serbian Cyrillic: Јелена Генчић, ] ; 9 October 1936 – 1 June 2013) was a Serbian tennis and handball player and coach.  In the 1970s she became a junior tennis coach and was later credited for playing a major role in the early development of numerous top class professional players and future grand slam champions.  Among the players she discovered and coached are Monica Seles, Novak Djokovic, Goran Ivanišević, Mima Jaušovec, Iva Majoli, and Tatjana Ječmenica. 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. Goran Ivanišević (; born 13 September 1971) is a retired Croatian professional tennis player and current tennis coach.  He is the only person to win the men's singles title at Wimbledon as a wildcard.  He achieved this in 2001, having previously been runner-up at the championships in 1992, 1994 and 1998.  Before the 2001 tournament, he was ranked 125th and after his victory he was 16th.  His career-high singles ranking was World No. 2 (behind Pete Sampras) in 1994.  He coached Marin Čilić from September 2013 to July 2016, leading Čilić to his biggest achievement to date, the 2014 US Open title. 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. The 1993 Paris Open was a tennis tournament played on indoor carpet courts.  It was the 22nd edition of the Paris Masters, and was part of the ATP Super 9 of the 1993 ATP Tour.  It took place at the Palais omnisports de Paris-Bercy in Paris, France, from 1 November through 8 November 1993. ' Goran Ivanišević won the singles title. Thomas Muster (born 2 October 1967) is a former World No. 1 tennis player from Austria.  One of the world's leading clay court players in the 1990s, he won the 1995 French Open and at his peak was known as "The King of Clay."  In addition, he won eight Masters 1000 series titles.  Muster is one of only three players to win Masters titles on the three different surfaces of clay, carpet, and hard court. Goran Ivanišević was the defending champion but lost in the final 7–5, 7–6 (7–3) against Thomas Muster.
Answer: Thomas Muster