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Twenty-year-old righthander Denis Kudla improved his ranking from No. 276 at the end of 2011 to his current career-high of No. 137 after posting excellent results on the USTA Pro Circuit this year. Kudla advanced to the quarterfinals or better at six Challenger events, winning titles at Lexington, Ky., and Charlottesville, Va., and reaching quarterfinals at Honolulu, Dallas, Tiburon, Calif., and Knoxville, Tenn.