MEMPHIS, Feb. 12 (UPI) -- Alex Bogomolov upset sixth-seeded American Sam Querrey in Tuesday's first round of the U.S. National Indoor Championships in Memphis.
Bogomolov withstood 18 aces from Querrey, the 2010 tournament champion, and claimed a 2-6, 6-4, 7-6 (9-7) win that sent him on to the second round.
Eighth-seeded Mikhail Kukushkin of Kazakhstan topped Russia's Teymuraz Gabashvili 7-6 (11-9), 7-5. Jack Sock of the United States also advanced with a 7-5, 1-6, 7-6 (7-5) victory of Adrian Mannarino of France.
Benjamin Becker of Germany defeated Lukas Lako of Slovakia 6-3, 6-2 and will face defending champion and No. 1 seed Kei Nishikori of Japan in the round of 16.