By TERESA M. WALKER
AP Sports Writer
MEMPHIS, Tenn. (AP) - Defending champion Kei Nishikori of Japan beat Benjamin Becker of Germany 6-4, 6-4 on Wednesday night in the U.S. National Indoor Tennis Championships.
Nishikori, who won his third career title at The Racquet Club last year, will play Russian Alex Bogomolov Jr. in the quarterfinals Friday. Bogomolov beat American Ryan Harrison 6-3, 2-6, 6-2 earlier Wednesday.
The defending champ started slowly as he struggled with his serve. Nishikori, who didn't drop a set here winning this tournament a year ago, jumped out to a 3-1 lead only to be broken twice. Nishikori broke Becker to open the match and again after the German broke him for a second time to tie the set at 4-4.
American Jack Sock beat Jiri Vesely of the Czech Republic 6-2, 6-1. Michael Russell downed fellow American Tim Smyczek 6-2, 7-6 (5).