Having trailed 4-0 and faced four further break points, Evans won six straight games to beat Khachanov 6-7(6), 7-6(2), 7-6(4), 4-6, 6-4 in five hours and 34 minutes.

Meanwhile, British No.1s Katie Boulter and Jack Draper punched their tickets into the second round of the US Open on a busy day for the Brits.

Boulter had to battle back from a set down to defeat qualifier Aliaksandra Sasnovich 5-7, 6-2, 6-1.

It was more straight forward for Draper, who progressed into the next round after world No.41 Zhizhen Zhang retired with the Brit leading 6-3, 6-0, 4-0.

Evans makes history in New York

Evans rose to the occasion out on Court 6 and played arguably his best match of the season against Khachanov.

Despite losing the opening set tie-break having had two set points at 6-4, and then going a break down late in the second set, Evans continued to fight.

His variety and impressive hands around the net made life increasingly difficult for the 23^rd seed and Evans went on to take the second set, before a second serve ace helped him clinch the third tie-break of the match.

Now leading, the pressure was on, but a poor service game at 4-4 in the fourth – including back-to-back double faults – gave Khachanov the platform needed to force a decider.

As the clock ticked towards and past the five-hour mark, Evans looked out of the match at 4-0 behind and another four break points on the Brits’ serve – but one hold seemed to give him the energy to push on. As Evans kept the scoreboard ticking over, the nerves seemed to take over the 23^rd seed who made error after error.

Having edged in front for the first time in the set, Evans produced some magic on his third match point to clinch an almost impossible victory and extend his winning record against the Russian to 5-0.

“I haven’t played a bunch of tennis this year, I just tried to keep fighting,” he said.

“At 4-0 I thought I was out – I felt a little sorry for myself and was trying to get myself going. I didn’t want to go out of another slam with not much fight and I could see he was struggling a bit. I’ve got a bad headache now so I’ve got to get rid of that.

“I’m really happy, it was a hell of a match. It was amazing, at 4-2 (the crowd) really started going. I don’t know how many British people are here, but it seemed like everybody wanted me to win and I don’t think that’s ever happened before.”

Evans will play world No.36 Mariano Navone in the next round.

Boulter fights off Sasnovich

Boulter came into her first round match in mixed form and it took a little while for her to get going against an opponent who had already come through three matches in qualifying.

Facing Sasnovich’s unorthodox serving style, the Brit lost the opening set but eventually started to re-discover her game and proved the more clinical of the two in the final sets.

The world No.107 failed to convert on six break points in the deciding set, whilst Boulter managed to complete a double break of her own to win the match in two hours and 26 minutes.

“It’s not easy coming out here first round and playing someone who’s been top 30, she knows how to play tennis,” Boulter told Sky Sports after her match.

“I knew it was going to be a battle, she’s played three matches on these courts. I feel like I came out really well and she responded quickly in the first set, and I didn’t quite get over that line, so I just had to reset.

“I'm super proud I managed to stay in there and bring a good level to the court.”

Boulter joins Billie Jean King Cup teammate Harriet Dart in the second round and will play either Jessica Bouzas Maneiro or Petra Martic.

Draper eases into round two

After a difficult week, Draper will have been pleased to get through his opening round match against Zhang in just 66 minutes.

In the first meeting between the two, the Cincinnati Open quarter-finalist got off to a lightning start – dropping just two points on serve to win the first set.

However, Zhang had been nursing a knee injury and after two medical timeouts, he was forced to retire having lost 12 straight games.

“I think today, I know he got injured and stuff, but I was ready to play my best tennis out there and I felt really, really good about myself,” Draper said.

“It’s always difficult to play someone who’s injured and slashing at the ball. But from my point of view, my last three grand slams, my first round matches have been five sets so it’s kind of a nice feeling to maybe have one that was a little bit easier, and hopefully can settle me in.”

Draper had his best career Grand Slam appearance at Flushing Meadows last year – reaching the fourth round. He will play Argentina’s Facundo Diaz Acosta next before a potential clash with Carlos Alcaraz.