Kei Nishikori, Marin Cilic Book US Open Finals Rematch

Japan's fifth-ranked Kei Nishikori and Croatia's eighth-ranked Marin Cilic booked a rematch of last year's US Open final by advancing Friday to the ATP and WTA Washington Open semi-finals.

And Nishikori made it clear he seeks a measure of revenge for Cilic denying his bid to become the first Asian man to win a Grand Slam title.

Reigning US Open champion Cilic defeated German teen Alexander Zverev 7-5, 7-6 (7/3) while Nishikori, the top remaining seed after Britain's Andy Murray crashed out, ousted Australia's Sam Groth 6-4, 6-4 in quarter-final matches.

That set up their first meeting since Cilic downed Nishikori 6-3, 6-3, 6-3, at Arthur Ashe Stadium last September for his first Grand Slam crown.

"It's going to be great motivation for me," Nishikori said. "I think it's going to be very interesting."

Nishikori, who has a 5-3 edge on Cilic in their all-time rivalry, said he recalls not being at his best for the biggest moment of his career thus far and welcomes another chance at the man who frustrated his dream.

"I was really nervous and I wasn't really into the match," Nishikori said. "Physically I wasn't 100 percent.

"I'm a better player than last year. I'm a little more solid baseline player. I'm a more aggressive player than before. I think I'm getting better. It's going to be a good match tomorrow."

Later quarter-finals at the US Open hardcourt warm-up event send US eighth seed John Isner against Lithuania's Ricardas Berankis and Jack Sock against Steve Johnson in Washington's first all-US quarter-final since 2003.

Nishikori is chasing his third title of the year after Memphis and Barcelona and the 10th of his career. The 25-year-old Asian number one has reached his seventh ATP semi-final of the year.

Nishikori took advantage of his fifth break chance in the seventh game, grabbing a 4-3 lead when Groth hit a forehand drop volley wide, and held twice more to take the first set in 39 minutes.

Groth, ranked a career-best 62nd this week, denied Nishikori on three break points to hold in the opening game of the second set, but Groth's fourth double fault of the match later gifted Nishikori a break for a 3-2 edge.

- Not easy for Nishikori -

Nishikori denied Groth on two break points in the eighth game and held at love in the final game to ende matters after 86 minutes.

"It wasn't easy," Nishikori said. "He has a great serve. It's never easy to face someone new but I thought I handled it well. Some of his first serves I had to let go. They were too good. Second serves I tried to attack and I did that really well."

Groth, whose only ATP semi-final was last year at Newport, fired 15 aces but fell to 0-4 against top-10 foes.

Cilic broke in the last game of the first set and the second game of the second set and served for the match before Zverev broke back.

In the tie-breaker, Cilic led 4-3 then hit a forehand winner and his eighth ace before Zverev netted a forehand to end it.

Cilic reached only his second semi-final of the year, matching a run on Stuttgart grass.

On the women's side, Australian second seed Samantha Stosur advanced when Romania's Monica Niculescu retired with a left abdominal strain down 0-4. Stosur plays American Sloane Stephens next in a shock run for the Aussie after a clay title two weeks ago in Austria.

"Probably a little bit surprised," Stosur said. "Started hitting on hardcourts last Thursday. Didn't feel ready to play in a lot of ways. I've been able to adapt really well."