Unseeded John Isner hit 20 aces with just three double faults and rallied to a 4-6, 6-3, 7-6 (4) quarterfinal victory over top seed Tommy Paul in an all-American showdown at the Infosys Hall of Fame Open on Friday in Newport, R.I.
Isner - who has won the tournament four times, most recently in 2019 - saw Paul narrow the third-set tiebreaker score from 5-2 to 5-4 before holding serve and winning on his first match point. Isner saved six of eight break points, while Paul saved five of seven and hit 13 aces with seven double faults.
The other quarterfinal match of the day also saw an upset, as unseeded Alex Michelsen took down No. 4 Mackenzie McDonald 6-3, 6-3. Michelsen won 81.6 percent of his first-service points (31 of 38).
Isner and Michelsen will meet in one semifinal match, with No. 2 seed Adrian Mannarino and No. 3 seed Ugo Humbert, both of France, set to contest the other.
The top four seeds, led by No. 1 Casper Ruud of Norway, all reached the semifinals in Bastad, Sweden.
Ruud beat Austria's Sebastian Ofner 6-3, 6-4, by winning all four of his break-point opportunities and 27 of his 33 first-service points (81.8 percent).
In the semifinals, Ruud will face No. 3 Lorenzo Musetti of Italy, the only winner Friday who needed three sets. Musetti rallied past Austrian qualifier Filip Misolic 4-6, 6-1, 6-2.
The other semifinal will pit No. 2 seed Andrey Rublev of Russia against No. 4 seed Francisco Cerundolo of Argentina. Rublev took care of fifth seed Alexander Zverev of Germany 6-2, 6-3, while Cerundolo beat countryman Federico Coria 6-3, 6-3.
EFG Swiss Open Gstaad
No. 2 seed Miomir Kecmanovic of Serbia beat Belgian qualifier Zizou Bergs 6-4, 3-6, 7-5 to advance to the semifinals in Gstaad, Switzerland.
Kecmanovic is the only seeded player remaining after his countryman, qualifier Hamad Medjedovic, upset No. 4 Yannick Hanfmann of Germany 6-3, 6-3.
Kecmanovic will face Albert Ramos-Vinolas in the semifinals after the Spaniard beat Peru's Juan Pablo Varillas 6-7 (2), 6-1, 6-4. Medjedovic will face Argentina's Pedro Cachin, who took down Jaume Munar 6-3, 6-3 one day after upsetting another Spaniard, Roberto Bautista Agut, the top seed.
--Field Level Media