MONTREAL (AP) Kei Nishikori beat Pablo Andujar 6-3, 6-3 on Wednesday in the ATP Tour's Rogers Cup in his first match since winning the Citi Open last week in Washington.
The fourth-seeded Nishikori, a finalist last year in the U.S. Open, earned his tour-leading 27th hardcourt win of the season in the second-round match that was delayed nearly 90 minutes by rain.
''I'm going to try to go to the final again, but I know it's a new U.S. Open this year,'' the Japanese star said. ''Just playing one match at a time and trying to focus from first match, and see what I can do again.''
At five foot 11, he's shorter than most of the best players of his generation.
''It's never easy,'' Nishikori said. ''If you face big servers, like last week I played John (Isner) and (Marin) Cilic, it's not much fun on the court.
''But I have a good return. I have good speed, too, that most of the big guys don't have. I think that's the fun things for tennis. You know, everybody's different. Even if you're small like me or David (Goffin).''
Goffin, seeded 13th, will be Nishikori's opponent in the round of 16 on Thursday. Goffin beat Sam Querrey 6-4, 6-4.
Seventh-seeded Rafael Nadal, coming off a victory on clay at Hamburg two weeks ago, got his tournament started with a 7-6 (4), 6-3 victory over Sergiy Stakhovsky.
The winner of 14 career grand slam events has slipped to ninth in the world after an up-and-down year. But back to full health, Nadal hopes to climb back to the top.
''I won in Hamburg a couple weeks ago and this was an important victory here,'' he said. ''Six consecutive (match) victories, that didn't happen very often during the season. That's a positive moment for me. Let's try to continue with that.''
Nadal will face Mikhail Youzny, a 6-1, 6-4 winner over ninth-seeded Gilles Simon.
Second-seeded Andy Murray beat Tommy Robredo 6-4, 7-5 in a rain-delayed match that started Tuesday night. Third-seeded Stan Wawrinka retired in the third set against Nick Kyrgios because of a lower-back injury in the final singles match of the night. Kyrgios led 6-7 (8), 6-3, 4-0 when Wawrinka stopped playing.
American Jack Sock downed 14th-seeded Grigor Dimitrov 5-7, 7-6 (5), 7-5 to advance to a meeting with top-seeded Novak Djokovic.
Defending champion Jo-Wilfried Tsonga, seeded 10th, outlasted Roberto Bautista Agut 5-7, 7-6 (6), 7-5.
The sixth-seeded Cilic dropped out, falling 6-3, 6-4 to Bernard Tomic.
Donald Young topped fifth-seeded Tomas Berdych 7-6 (5), 6-3, and Isner beat Vasek Pospisil 7-6 (1), 4-6, 6-3, eliminating the last Canadian from the singles draw.
Jeremy Chardy topped Leonardo Mayer 6-4, 7-6 (4) to set up a third-round meeting with 6-foot-11 Ivo Karlovic.