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Marin Cilic (Croatian pronunciation: [mari:n tSi:litc]; born 28 September 1988) is a Croatian professional tennis player. Over the course of his career, Cilic has won 17 ATP singles titles, including the 2014 US Open. His career-high singles ranking is world No. 3, achieved on 28 January 2018. Cilic first came to international prominence by defeating then-World No. 2 Andy Murray in the fourth round of the 2009 US Open, and then reaching the semi-finals at the Australian Open a few months later.

Cilic won the 2010 Chennai Open final, beating Stanislas Wawrinka of Switzerland in straight sets.  Seeded 14th at the 2010 Australian Open, he defeated Fabrice Santoro, Bernard Tomic, and Stanislas Wawrinka in the first three rounds. In the fourth round, he faced fourth seed and reigning US Open champion Juan Martin del Potro; it was their third meeting in the past five Grand Slams. In a match that lasted more than four and a half hours, Cilic defeated Del Potro to reach his second quarterfinal appearance at a Grand Slam. In the quarterfinals, he defeated seventh seed Andy Roddick in another five-set victory. In doing so, he became the first Croatian to reach the semifinals at the Australian Open. However, Cilic eventually lost in four sets to Andy Murray, despite winning the first set. Cilic followed up his Australian campaign by defending his title in Zagreb, defeating Michael Berrer in the final. Cilic achieved a new career-high ranking of no. 9 as a result. Cilic was selected to play singles and doubles partnering with Karlovic for the Croatia Davis Cup Team against Ecuador in March 2010. Cilic, seeded eighth, lost in the second round to Guillermo Garcia-Lopez at the 2010 BNP Paribas Open.  At the French Open, Cilic lost to Robin Soderling in the fourth round. Cilic was defeated in the first round of Wimbledon by Florian Mayer.  He reached the semifinals of the Legg Mason Tennis Classic in Washington, D.C., ending Mardy Fish's 11-match winning-streak in the third round. Cilic was defeated by eventual champion David Nalbandian.  At the US Open, Cilic lost to Kei Nishikori in the second round.

Entity:
Marin Čilić