Friday 22 July 2016 14:40, UK
Dan Evans suffered a third-round exit at the Citi Open in Washington after going down to a straight-sets defeat to sixth seed Jack Sock.
The British No 4 enjoyed impressive wins over Benjamin Becker and Grigor Dimitrov but he struggled against the big-serving American, who won 23 of 25 first-serve points in the 6-1 7-5 victory.
Evans quickly slipped 5-0 behind in the opening set against the world No 26 and although he avoided being blanked he was also made to work to stay in the second set.
Evans saved two early break points and then failed to take advantage of a set point on Sock's serve at 5-4.
He then failed to convert a game point in the next game as he was broken by Sock, who then served out for victory in just under 76 minutes.
Top seed John Isner is also safely through after a 7-6 6-2 win over Marcos Baghdatis and was joined in the next stage by the second seeded Gael Monfils, who claimed a 6-2 6-3 victory over Borna Coric.
In other third round results, fifth seed Steve Johnson won his all-American battle with Ryan Harrison, while seventh seed Alexander Zverev beat Malek Jaziri and Sam Querrey defeated Alexandr Dolgopolov.
Quarter-finals (from 6pm BST on Friday):
Ivo Karlovic v Jack Sock
John Isner v Steve Johnson
Sam Querrey v Gael Monfils
Alexander Zverev v Benoit Paire
Watch live coverage of the Citi Open in Washington DC on Sky Sports 5 HD from 6pm on Friday.