WASHINGTON — Kei Nishikori withstood 15 aces and managed to break Sam Groth's big serve twice for a 6-4, 6-4 victory in the Citi Open quarterfinals Friday.
"Some of them I couldn't really see," Nishikori said about Groth's serves. "When it was 145 or 147 (mph), even if I guessed, it was too fast, so it wasn't easy to return."
The second-seeded Nishikori, last year's runner-up at the U.S. Open, saved all four break points he faced en route to reaching a tournament's semifinals for the sixth time this season — and first in five appearances at the hard-court event in Washington.