Question: Which tennis player received a higher world singles ranking, Fabio Fognini or Marin Čilić?
Context: David Goffin (] ) (born 7 December 1990) is a Belgian professional tennis player who is currently ranked world No. 12 in men's singles by the Association of Tennis Professionals (ATP).  He was born in Rocourt, Liège, Belgium.  His breakthrough came when he reached the fourth round of the 2012 French Open as a lucky loser, eventually losing to Roger Federer in four sets.  Goffin has defeated several higher-ranked players such as John Isner, Stan Wawrinka, Novak Djokovic, Marin Čilić, Milos Raonic, Jo-Wilfried Tsonga, Dominic Thiem and Tomáš Berdych, the latter without losing a game.  He is the Belgian number 1 male tennis player as of 2017.  On February 20, 2017 Goffin became the first Belgian male tennis player to reach the ATP top 10. Marin Čilić (; born 28 September 1988) is a Croatian professional tennis player.  Over the course of his career, Čilić has won 17 ATP singles titles, including the 2014 US Open.  His career-high singles ranking is world No. 5, achieved in September 2017.  Čilić first came to international prominence by defeating then-World No. 2 Andy Murray in the fourth round of the 2009 US Open.  He followed this by reaching the semifinals of the 2010 Australian Open.  Among other achievements, Čilić was runner-up at the 2017 Wimbledon Championships, and was a semifinalist at the 2015 US Open as defending champion.  Čilić is currently the youngest active male player to have won a slam.  Čilić has reached at least the quarterfinal in all four grand slam tournaments.  He has a very powerful serve and very powerful groundstrokes. 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. Adam Pavlásek (born 8 October 1994) is a tennis player playing on the ATP Challenger Tour from the Czech Republic.  He reached his career-high ATP singles ranking of World No. 72 in January 2017.  At the start of 2015, Pavlásek replaced injured countryman Radek Štěpánek in the Hopman Cup, playing alongside Lucie Šafářová.  He made a name for himself by defeating world number 20 Fabio Fognini of Italy, Pavlásek's first ever win over a top 20 player. 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. This is a list of the main career statistics of Croatian professional tennis player, Marin Čilić.  To date, Čilić has won 16 ATP singles titles including one grand slam singles title at the 2014 US Open, one ATP Masters 1000 title at the 2016 Western & Southern Open and a record four titles at the PBZ Zagreb Indoors.  Other highlights of Čilić's career thus far include a semi-final appearance at the 2010 Australian Open and three consecutive quarterfinals at the Wimbledon Championships from 2014 to 2016.  Čilić achieved a career high singles ranking of World No. 6 on November 21st, 2016. Paolo Lorenzi (] ; born 15 December 1981 in Rome, Italy) is an Italian professional tennis player, and current Italian No. 2.  His career-high singles ranking is World No. 33.  Lorenzi is coached by Claudio Galoppini.  On August 1, 2016 he overtook Fabio Fognini becoming the new Italian #1 in the Association of Tennis Professionals ATP Ranking at the age of 34 years old and 8 months. 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. Marinko Matosevic (Croatian: "Matošević" ; born 8 August 1985) is an Australian professional tennis player.  His career-high singles ranking is World No. 39, which he achieved in February 2013.  Matosevic has defeated top players including Milos Raonic, Marin Čilić, Nikolay Davydenko, Jo-Wilfried Tsonga and John Isner. Óscar Serrano Gámez (born 25 May 1978, in Barcelona, Catalonia) is a former Spanish professional male tennis player.  Currently, as June 2010, Oscar Serrano is the coach of Fabio Fognini.
Answer: Marin Čilić