Kyle Edmund reached his first ATP Tour semi-final in nine months, after beating top seed Jack Sock at the BB&T Atlanta Open in Georgia.
The 22-year-old Brit reeled off nine of the last 10 games, as he cruised to a 6-4 6-1 victory over the world No 19.
Edmund appeared to be helped by a 20-minute break in play, when one of the spectators required medical attention.
Having been a break down at this stage, the Yorkshire player suddenly found his best form when the action resumed and he wrapped up a well-deserved triumph in 88 minutes.
In his last five service games, the No 5-seeded Edmund conceded just two points to set up a semi-final encounter with another American – Ryan Harrison.
The No 4 seed from Louisiana beat his unseeded compatriot Christopher Eubanks 6-1 6-2 in under an hour.
Harrison, 24, did not offer his opponent a single break point opportunity and, at No 42 in the world, is ranked just three spots higher than Edmund.
Looking ahead to his next match on Saturday, Harrison said: “Kyle was playing some amazing tennis at the end of last year and has shown some highlights of that throughout this year as well.
“I’m going to focus on doing what I can to get myself and my body ready to go. If I can do that and serve well, I’ll have a chance.”
The other semi-final features the experienced pair of John Isner and Gilles Muller.
The No 2-seeded Isner – who won last week’s grass court event on Rhode Island – defeated Slovakian Lukas Lacko 7-5 6-4 in a match that featured just a single break of serve in each set.
As for Muller, the No 3 seed from Luxembourg, he eased past American Tommy Paul 6-3 6-1 in 71 minutes.
We will have the Masters 1000 series in Montreal and Cincinnati covered via our website skysports.com/tennis and you will also be able to watch all the action live on Sky Sports.
On the move? Head to our app for mobile devices and iPad, or follow our Twitter account @SkySportsTennis to join in the conversation. Who will win the US Open titles this year? Have your say…