Question: Which tennis player, Marion Bartoli or Geoff Masters, had a more prominent career in singles tennis matches?
Context: Tathiana Garbin (born 30 June 1977) is an Italian retired tennis player.  Garbin is probably best known for her surprise defeat of the defending champion and the reigning World No. 1 Justine Henin in the second round of the 2004 French Open.  The winner of one singles and eleven doubles WTA Tour titles, she reached her highest singles ranking World No. 22 on 21 May 2007, and her highest doubles ranking World No. 25 on 27 August 2001.  Other high–ranked players she defeated include Jelena Dokić, Chanda Rubin, Flavia Pennetta, Agnieszka Radwańska, Nadia Petrova, Marion Bartoli and Samantha Stosur. 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. Since the initiation of the Fed Cup tournament 1963, 44 tennis players have reperesented the Australia Fed Cup team in ties.  A Fed Cup tie is a contest involving four singles tennis matches and one doubles match in World Group and World Group II competitions from 1995 onwards, and two singles and one doubles matches elsewhere, competed between two Class B members of the ITF.  Fed Cup differs from Davis Cup in that ties are played over two days rather than three, that the doubles match is played fifth rather than third, that matches are always best-of-three, and that zonal competition ties never have more than three matches. The 2006 Challenge Bell was a tennis tournament played on indoor carpet courts at the PEPS de l'Université Laval in Quebec City in Canada that was part of Tier III of the 2006 WTA Tour.  It was the 14th edition of the Challenge Bell, and was held from October 30 through November 5, 2006.  Marion Bartoli won the singles title. Petra Cetkovská (] ; born 8 February 1985 in Prostějov, Czechoslovakia) is a professional tennis player from the Czech Republic.  She reached her career-high singles ranking world no. 25 in June 2012.  Over her career, Cetkovská has beaten top players: Marion Bartoli, Elena Dementieva, Ana Ivanovic, Angelique Kerber, Li Na, Agnieszka Radwańska, Caroline Wozniacki, and Vera Zvonareva. Geoff Masters (born 19 September 1950) is an Australian former tennis player.  He was part of doubles winning pairs in the US Open, Australian Open and Wimbledon tournaments during the 1970s. Aravane Rezaï (] ; Persian: ارغوان رضایی‎ ‎ "Arghavān-e Rezāyi" ] , born 14 March 1987) is an Iranian–French tennis player.  She has defeated many top players on the WTA circuit, such as Justine Henin, Venus Williams, Victoria Azarenka, Maria Sharapova, Dinara Safina, Francesca Schiavone, Caroline Wozniacki, Marion Bartoli, Flavia Pennetta, Jelena Janković and Ai Sugiyama.  Her career high rank was No. 15, achieved on 11 October 2010. This is a list of the main career statistics of tennis player Marion Bartoli. Ekaterina Makarova was the defending champion, but lost to Petra Kvitová in the second round.  Kvitová eventually lost the final 1–6, 6–4, 5–7 to Frenchwoman Marion Bartoli.  It was Bartoli's first title of the year and sixth of her career.  It was her second Premier-level career title and first on grass courts. Jill N. Craybas (born July 4, 1974) is an American former professional tennis player.  At 39 years of age, she was one of the oldest players on the WTA Tour, as well as the longest serving, having turned pro in 1996.  From the 2000 US Open to the 2011 US Open, Craybas competed in 45 consecutive Grand Slam main draws, her best result coming in the 2005 Wimbledon Championships where she reached the fourth round which included wins over Marion Bartoli and Serena Williams.
Answer: Marion Bartoli