Defending champion Kei Nishikori will face Sam Querrey in the semi-finals of the Memphis Open after beating Mikhail Kukushkin 6-2, 6-4.
The top seed, who is a three-time champion at the event, needed an hour and 31 minutes to see off Kukushkin, easing through the first set on the back of two breaks of serve before being made to work harder for the second set.
The fourth-seeded Querrey beat Japanese qualifier Yoshihito Nishioka 6-3, 6-4 earlier on Friday to secure his spot in the last four.
It was teenager Taylor Fritz who stole the headlines though.
The 18-year-old became the youngest American to reach the semi-final of an ATP Tour event since Michael Chang won at Wembley in 1989 at the age of 17 when he downed Benjamin Becker 6-4, 5-7, 7-6 (5).
“It’s incredible,” Fritz said. “I can’t believe it. Just an amazing feeling, especially after the match I just had coming back … he was serving for the match and to come back and win it in that way and tough it out, I’ll never forget that.”
Fritz will face Ricardas Berankis of Lithuania in Saturday’s semi-final after Berankis upset third seed Donald Young 7-6, 6-1.