Kei Nishikori exacted a measure of revenge against Marin Cilic when the Japanese world number five overcame the Croatian in the semi-finals of the Citi Open tennis tournament in Washington DC.

Cilic beat Nishkori in the US Open final last year, but after a dismal start the Japanese prevailed 3-6, 6-1, 6-4.

"I had to make some changes," Nishikori said.

"He was playing very well at the start. I raised my game in the second set."

Nishikori will meet American John Isner, who survived a tough challenge from compatriot Steve Johnson in the second semi-final.

Isner defeated the unseeded Johnson 6-3, 3-6, 7-6.

The 25-year-old Nishikori will be chasing his third win of the year and and is already assured of moving up a notch to fourth in the world rankings.

Nishikori, who has now beaten Cilic in six of their nine head-to-head matches, improved his match record this year to 42-9. Only Novak Djokovic (48-3) and Andy Murray (48-8) have more wins on the 2015 ATP World Tour.

Source: Reuters