Falla routed sixth-seeded Gilles Simon 6-1, 6-0 in 66 minutes. He won 63 percent of the points off Simon's serve and converted six of his nine break opportunities over seven games.
Falla fought off all five break points he faced and took 61 percent of the points when serving.
No. 3-seeded Nicolas Almagro lost nine points in his eight games serving during a 6-2, 6-3 win over Pablo Andujar. Four of those points came in a second-set game in which he saw the only break point Andujar managed Tuesday. Almagro won 16-of-18 points when serving in the first set.
Fifth-seeded Jerzy Janowicz edged past Pablo Carreno Busta 7-5, 7-6 (9-7) while Julien Benneteau topped Feliciano Lopez 6-3, 6-1 and Michal Przysiezny was a 6-3, 7-6 (7-1) winner over Fernando Verdasco. Mikhail Youzhny advanced when, after Youzhny built a 4-1 lead in the third set, Bernard Tomic retired.
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