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Denis Istomin achieved his career-high singles ranking of world No. 33 on 27 August 2012. Istomin had a breakthrough season in 2012, reaching the third round of the Australian Open, the quarterfinals of the French Open, and the quarterfinals of Wimbledon. He also won his first ATP title at the 2012 Winston-Salem Open. Istomin has been ranked in the top 50 since 2012.