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Jesse Levine coached Madison Keys from 2015 to 2016. Levine is a former professional tennis player who reached a career-high singles ranking of world No. 67 in 2009. He began coaching Keys in 2015, and under his guidance, she reached a career-high ranking of world No. 7 in 2016. Keys won her first WTA title in 2014 and has since won six WTA singles titles.