Hyeon Chung’s incredible run at the Australian Open men’s singles will stretch into the semi finals.

The 58th ranked South Korean produced another efficient performance to beat American surprise packet Tennys Sandgren 6-4 7-6 (5) 6-3 in straight sets at Rod Laver Arena on Wednesday afternoon.

Chung has only dropped two sets this whole tournament and appears at ease on court, almost like he is not grasping the enormity of his situation.

“I’m just trying to keep focus on the court and enjoy,” Chung said.

“That’s the key for today.”

Chung’s only stressful moments came in a second set tie breaker.

Like he has all tournament, the 21-year-old from Suwon found a way.

Chung went on to seal the match in 2 hours 28 minutes.

The most striking aspect of his game is his quick movement back and forth and willingness to attack at the net.

It is an aspect that Chung focused on in his preparations for this tournament.

“I’m just trying to work on playing on the net,” he said.

“In the pre-season and all the time when I practice, I’m just trying to playing more in the net. If I going to the net, I can save more energy.”

While Chung’s focus is on his challenges in Australia, he can’t avoid questions about his rising stardom back home in South Korea.

Asked if he is becoming more famous in his homeland, he responded: “I think sure, yeah, getting better and better all the time now”.

This was a match for the real underdogs.

If people were shocked by Chung’s appearance at the quarter final stage, they would have been doubly so by Sandgren’s name bobbing up.

Sandgren ended last year 96th on the ATP rankings, but he can expect to see that rise after his breakthrough tournament.

The 26-year-old admitted the grueling tournament had finally taken its toll after an “amazing” run to the quarters.

“Yes, maybe a little tired,” Sandgren said.

“The net felt like it was about 12 feet high today. Just struggling to serve the way that I wanted to. But I also knew that I had to serve well and serve to my spots correctly because he returns so well. I think that played a factor in it as well.”

Sandren collected a number of big scalps along the way, including top 10 seeds Stan Wawrinka and Dominic Thiem.