Jacob Fearnley provided a bright end to a disappointing day for Britain at the US Open despite serving 18 double faults in a debut victory.

The Scot admitted nerves got the better of him as he tried to close out a late-night victory against Roberto Bautista Agut, but he regrouped to claim a 7-5 6-2 5-7 6-4 win.

After defeats for Katie Boulter, Sonay Kartal, Fran Jones and Billy Harris earlier, Fearnley was relieved to avoid a blank for British players as he joined Jack Draper, Emma Raducanu and Cameron Norrie in round two.

“I’m pretty tired right now,” said Fearnley. “I don’t really know what to make of it. Obviously to get over the line is really good. I was playing great first two sets and then got a little bit nervous and Roberto makes you earn it. When you’re nervous, that’s going to have its effect.”

Fearnley’s service woes began early on but reached a nadir in the third set, where he was broken three times and hit eight double faults, nearly all at crucial moments.

“I think it’s definitely nerves,” said the 23-year-old. “Obviously you’re going to double fault, you’re never not going to double fault, but 18, that’s too much. If you look at when the double faults are happening, it’s when I’m serving for the match, serving to stay in the set. It’s at the highest tension moments.

“It’s helpful to know that even hitting all those double faults I can still win the match. That’s a positive. There’s good days, there’s bad days. In recent big matches, the double faults have been a little bit of an issue.”

The match was moved to the Grandstand court, the third biggest at Flushing Meadows, after the previous match on Court 12 where it had been originally scheduled went to a fifth set.

The crowd was sparse but they witnessed a very competitive first set, with Fearnley digging in to save a set point at 4-5 before breaking Spaniard Bautista Agut, who at 37 is one of the most experienced players on tour.

Fearnley relaxed into the contest and played a fine second set, leaving Bautista Agut sat on the advertising hoardings at the side of the court after one long baseline point.

When the British number three moved a break ahead in the third set, he looked poised to wrap up victory, but this is only his fifth grand slam tournament and the road became distinctly rocky.

He double faulted for a 16th time to lose the set – becoming unsettled by a vocal fan who switched from supporting him to his opponent – and then dropped serve again to start the fourth.

But he responded very well and eventually made it across the line after three hours and 24 minutes – the longest match of his career.

He believes more experience will help address the double fault issue, saying: “Even though I’ve had some pretty big match experience, it’s still all relatively new for me and being in these kind of moments and these matches, it still gives me a lot of nerves.

“Maybe more than it necessarily should. I’m sounding like I’m a nervous wreck, I’m not, I’m fine. Just sometimes in those big moments, I need to be a little bit more clear and that will come with experience. It’s not something I’m worried about.”