Atlanta, GA, USA, 6 August 2016 | AAP

Aussie young gun Nick Kyrgios has advanced to the semifinals of the Atlanta Open as he seeks his second ATP Tour title.

Second-seeded Kyrgios, who claimed his first title in Marseille, in February, worked hard to get past Spanish fifth seed Fernando Verdasco 6-4 6-7(5) 6-2 in oppressive conditions, with the temperature in the mid 30s and the humidity up in America’s deep south.

It took Kyrgios just under two hours to dispose of the veteran Spaniard, the Aussie’s big serve on song as he banged down 18 aces in a serving display that saw him rarely troubled.

In fact Kyrgios dropped just 10 points when his first serve went in and faced just one break point in the match, which he saved.

“It’s hot as anything out here,” Kyrgios said post match.

“We were both serving well, both hitting big and to be honest I was feeling pretty average towards the end and I’m just glad I got through.

“I’ve played matches where I have had to dig deep, come from two sets down at slams, so I know the feeling, today it was all mental.”

The Aussie will now play 20-year-old rising Japanese star Yoshihito Nishioka in the semis, after Nishioka breezed past Argentine veteran Horacio Zeballos 6-4 6-4 in his quarterfinal.

For Kyrgios, Nishioka represents a familiar opponent and he is wary of the world No.97, who sent Ukrainian veteran Alexandr Dolgopolov packing in the second round.

“We’re the same age, I grew up with him, played junior teams events with him, so I know him very well.

“I have played him before, he’s a great guy, was a great junior, he has transitioned well and has a great future ahead of him.”

Top seed John Isner is going for his fourth straight Atlanta title and will take on fellow American Taylor Fritz in his quarterfinal.