Delray Beach, FL, USA, 21 February 2015 | AFP/AAP

Bernard Tomic has defeated Yoshihito Nishioka and will face American Donald Young in the semifinals of the ATP Delray Beach Open in Florida.

Australia’s Tomic, playing his fourth quarterfinal of the season, ended the run of the 19-year-old Japanese qualifier 6-3 6-1.

Tomic saved all seven break points he faced to dismiss the 154th-ranked Nishioka in less than an hour.

Young toppled third-seeded Ukrainian Alexandr Dolgopolov 2-6 6-3 6-4 to book a showdown with Tomic.

World No.56 Young, withstood 11 aces from the 24th-ranked Dolgopolov in a match lasting one hour and 56 minutes.

“I thought I fought well,” said the American, who remains in search of a first ATP tour title.

“I didn’t start off the way I wanted to. He was playing pretty well, hitting through the wind and controlling his shots quite good. I decided to buckle down, fight, go out swinging and got a little more not so conservative and it happened to work.”

Young reached his fifth tour-level semifinal and his second in as many weeks after making the final four at Memphis.