Roddick was serving at 1-4, love-40 in the first set when he rallied Tuesday on the strength of his dominating serve. He won 34 of his final 39 service points, including all six in the tiebreaker.
Roddick, who closed out the victory with his seventh ace, has won all nine sets he has played against Becker.
Seeded sixth, Roddick improved to 23-4 this year, and he leads the men's tour in wins. His only Key Biscayne title came in 2004.
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