ATLANTA (AFP) - Australia's Nick Kyrgios punched his ticket to tennis' Atlanta Open final on Saturday, by ending the remarkable run of young upstart Yoshihito Nishioka 6-3, 3-6, 6-3.

Playing in humid conditions, second-seeded Kyrgios blasted 16 aces to win the semi-final over the 20-year-old Japanese rising star in 96 minutes.

The 21-year-old advances to his third ATP Tour final of his career, where he will face top seed John Isner, who defeated teenage wild card Reilly Opelka 6-7 (5-7), 6-4, 6-2 in the other semi-final.

"It was a hot and humid day," Kyrgios said. "Yoshi is a great player and makes you play a lot of balls and a lot of rallies. I came out strong (in the third set) and that shows good fighting spirit.

"It feels good. I knew at the start of the week that I could get this far. It's not really surprising, but it's for rewarding for sure."

Nishioka, played a strong second set to level the match before Kyrgios clinched the win in the third set. It was Japanese player's first semi-final of his career and ended his run of three straight wins in Atlanta.

He upset fourth seed Alexandr Dolgopolov in the second round 6-3, 2-6, 6-1.

"I think I played very well, but he has a great serve," Nishioka said of Kyrgios.

"He has a great second serve and I didn't have many chances to break. I couldn't put pressure on his first serves either."

In one of the "tallest" matches ATP men's tennis history, the 2.08m Isner beat fellow American Opelka, who stands at 2.11m.

The 31-year-old Isner has now reached the Atlanta final six times in seven appearances.

"I wish we could play every week in Atlanta," Isner said. "I think I'd be No. 1 in the world."

He hammered 22 aces while the 18-year-old Opelka, who is ranked 837th in the world, finished with four double faults and 15 aces.