Sam Querrey defeated Alejandro Falla of Columbia 6-3, 6-3 to move into the second round.
Tannen Maury/EPA

MEMPHIS, Tenn. (AP) -- Fourth-seeded Sam Querrey of the United States defeated Alejandro Falla of Columbia 6-3, 6-3 Tuesday, advancing to the second round of the U.S. National Indoor Tennis Championships.

Third-seeded John Isner of the United States and fifth-seed Kei Nishikori of Japan played their opening matches later Tuesday. Isner was to face Denis Istomin of Uzbekistan and Nishikori played qualifier Illya Marchenko of Ukraine.

In the women's draw, third-seeded Sabine Lisicki of Germany and seventh-seeded Magdalena Rybarikova of Slovakia both won their matches in straight sets. Lisicki defeated qualifier Madison Keys of the United States 7-5, 6-3, while Rybarikova beat American Lauren Davis 7-6 (2), 6-2.

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