Dan Evans' remarkable run at the US Open is over after falling to 19th seed Tommy Robredo in four sets.
The Briton, who had never won a match in the main draw of a grand slam before this week, had two set points on his own serve to take it to a decider but failed to convert either chance, and Robredo took advantage to see out the match 7-6 (6) 6-1 4-6 7-5.
It was British No. 3 Evans' sixth match in ten days at Flushing Meadows, having coming through three qualifiers before his run to the third round, which saw him beat 11th seed Kei Nishikori and world number 52 Bernard Tomic.
Evans looked as impressive as he had in the previous matches in the opening, taking Robredo to a tie break. But the Spaniard's experience came through as he nudged ahead, before racing through the second set in just 28 minutes.
But Evans battled back and, at 4-4 in the third, executed a slick backhand volley to get the vital break to take it the a fourth. In the ascendency, the 23-year-old twice broke to take a 5-3 lead. But, serving at 40-15, the nerves appeared to take control and he gave up the set points with a double fault and an unforced error before Robredo pounced.
"It was a tough one, especially to go down in the fourth set after serving for it and having two set points," Evans told BBC Sport.
"I felt in pretty much total control of the match. The last point is always the hardest one and I couldn't get that last point of the set to take it to a fifth.
"I just played two really loose points - that's all it was. They came at the wrong time. I just have to learn on that for next time."
Evans, ranked 179th in the world, earned £60,000 in prize money for his efforts and his run should see him pick up enough ranking points to move in to the top 150.
"It's been a great experience and a great learning curve," added Evans, who now heads to Croatia for Great Britain's Davis Cup tie on September 13.
"I can definitely play with these guys so I should be confident going into the next tournaments."
The defeat denied Evans a showdown with Roger Federer, who moved into the fourth round at the US Open for the 13th year in a row, racing through a 6-3 6-0 6-2 victory over 63rd-ranked Adrian Mannarino in 81 minutes.
Federer, looking back to his best, has spent just four and a half hours on court at this tournament, dropping only 21 games in total.
The 17-time grand slam champion, who won five consecutive US Opens from 2004, said: "You come to New York, and if you're not excited anymore, you're in the wrong place. You don't like the sport the way you should.
"If you don't put in 100 percent effort here or in other places that really you care about, then something's wrong with you. I'm just totally excited being here. I have always enjoyed playing here. I have never had a bad tournament at the US Open."
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