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World No. 4 was Štěpánek's peak doubles ranking, achieved in July 2013. He enjoyed a successful doubles career, winning 18 ATP titles alongside various partners, including Leander Paes, with whom he claimed two Grand Slam titles: the 2012 Australian Open and the 2012 French Open. Štěpánek also reached the finals of the 2013 US Open and the 2016 Wimbledon Championships.