Lucie Šafářová (] ; born 4 February 1987) is a Czech professional tennis player from Brno.
 She is currently the WTA world No. 1 doubles player.
 Šafářová has won seven WTA tour singles titles, fifteen doubles titles and reached the quarterfinals of the 2007 Australian Open by upsetting defending champion Amélie Mauresmo in the fourth round.
 She reached her first Grand Slam semifinal at the 2014 Wimbledon Championships and her first Grand Slam final at the 2015 French Open.
 She also won the 2015 Australian Open, 2015 French Open, 2016 US Open, 2017 Australian Open and 2017 French Open women's doubles titles partnering with Bethanie Mattek-Sands.
Simone Bolelli and Fabio Fognini were the defending champions but Bolelli decided not to participate.
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Fabio Fognini (] ; born 24 May 1987) is an Italian professional tennis player who is currently ranked world No. 29 in men's singles by the Association of Tennis Professionals (ATP) and the current Italian No. 1.
 His career-high singles ranking is world No. 13, achieved in March 2014, and world No. 7 in doubles, achieved in July 2015.
 Fognini's most successful surface is red clay, upon which he won his four ATP singles titles in Stuttgart, Hamburg, Viña del Mar and Umag, reached the quarterfinals of the 2011 French Open and the semifinals of the 2013 Monte-Carlo Masters.
 Together with Simone Bolelli, Fognini won the 2015 Australian Open doubles event, becoming the first all Italian men's pair to win a Grand Slam title in the Open era.
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.
Maria Fernanda Barbato Alves (born 17 April 1983), also known as Nanda Alves, is a Brazilian tennis player.
 She is currently coached by her father Carlos and former tennis player Thomaz Koch.
 As of 1 March 2010, Alves is ranked World No. 262, and is the highest ranked Brazilian player.
 She has enjoyed success at the ITF Circuit, winning 18 singles and 26 doubles titles so far.
 Alves made her WTA Tour debut at Copa Colsanitas in 2004, and has played qualifications for all four Grand Slam events.
 Partnering with Vanessa Henke, Alves took part in the 2005 Australian Open doubles event, but they lost to Daniela Hantuchová and Martina Navratilova in the first round.
Andrés Gimeno Tolaguera (born 3 August 1937) is a retired Spanish tennis player.
 His greatest achievement came in 1972, when he won the French Open.
Ekaterina Valeryevna Makarova (Russian: Екатери́на Вале́рьевна Мака́рова ; ] ; born on 7 June 1988) is a Russian professional tennis player.
 She achieved her career-high ranking of number 8 on 6 April 2015.
 Her best Grand Slam singles results have come at the 2014 US Open and the 2015 Australian Open where she reached the semifinals on both occasions.
 Makarova is a four-time Grand Slam champion in doubles competition, having won the 2012 US Open mixed doubles tournament with Bruno Soares, and the 2013 French Open, the 2014 US Open and 2017 Wimbledon Championships with Elena Vesnina.
Jiske Griffioen (born 17 April 1985) is a Dutch wheelchair tennis player.
 Griffioen is a thirteen-time Grand Slam champion in doubles and a three-time Paralympic medalist.
 She is also a seven-time Masters doubles champion and the current World number one.
 Alongside Aniek van Koot, Griffioen completed the Grand Slam in doubles in the 2013 season.
 In singles competition Griffioen is the 2012 Masters champion and the 2015 Australian Open, French Open and Masters champion and the current world number one.
Simone Bolelli (born 8 October 1985; ] ) is an Italian professional tennis player.
 Bolelli is a Grand Slam champion since he won the 2015 Australian Open doubles event with Fabio Fognini, becoming the first all Italian men's pair to win a Grand Slam title in the Open Era.
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.

Question: What tennis player, Simone Bolelli or  Andrés Gimeno Tolaguera, is a Grand Slam champion since he won the 2015 Australian Open doubles event with Fabio Fognini?
Answer: Simone Bolelli