Nishikori beats Cilic to reach Memphis semis

Croatia's Cilic had saved three match points in his previous match against Igor Sijsling, but could not find the answer against Nishikori, who had just four aces compared to a dozen for Cilic but won 69 percent of points on his serve.

"I was dominating with my serve," said the 23-year-old Nishikori, who also reached the semi-finals in Brisbane in January but retired from that match against Andy Murray with a knee injury.

Since then, he has reached the fourth round of the Australian Open.

"It's getting better every match... little by little," Nishikori said of his game.

He next faces Australian Marinko Matosevic, a 6-7 (6/8), 6-2, 6-4 winner over seventh-seeded Alexandr Dolgopolov of Ukraine.

Nishikori won their only prior meeting at Brisbane earlier this year.

The other men's semi-final in this combined ATP and WTA event will pit Spain's Feliciano Lopez against Uzbekistan's Denis Istoman.

Lopez defeated US wildcard Jack Sock 6-4, 6-3, and Istoman was a 6-4, 7-6 (7/5) winner over Michael Russell of the United States.

In women's action, big-hitting Sabine Lisicki of Germany set up a title showdown with Marina Erakovic.

Lisicki, the third seed, fell behind in each set but dug deep for a 7-5, 7-5 semi-final win over seventh-seeded Magdalena Rybarikova. She will be vying for a fourth career WTA title.

New Zealand's Erakovic defeated Stefanie Voegele of Switzerland 6-2, 6-4 to earn a shot at a first WTA title. She has two runner-up finishes on her resume, including in Memphis last year.