Daniel Evans swung his way into US Open history Tuesday, and he did so in unlikely fashion — despite entering the tournament without a victory in a grand slam this year and, at age 34, having seen his ranking fall all the way to No. 184 in the world.

But in his first match in Flushing, the veteran Brit didn’t just upset No. 23 Karen Khachanov.

He did so after falling behind 4-love in the fifth and final set in the longest match in Open history since tiebreakers were introduced in 1970.

“I was hurting all over really,” Evans said after his thrilling 6-7 (6), 7-6 (2), 7-6 (4), 4-6, 6-4 victory on Court 6 that lasted a record five hours and 35 minutes and included 392 total points. “I don’t think I’ve played five hours — that long — in a day ever in two sessions, never mind in one. I was actually thinking [about] that on the court. …

“I’m immensely proud that I came through the match. I think that’s the overriding feeling more than anything. I’ve had a lot of first rounds this year. It’s nice to win a match. … You always have doubts when you’ve been not winning. That’s normal in any walk of life. If you’re not doing well, you have doubts. It’s no different in tennis.”

The previous longest US Open match was five hours and 26 minutes.

That was a 1992 semifinal, in which Stefan Edberg ousted Michael Chang.

It was a draining match for both players. At one point in the fourth set, Evans checked the scoreboard to see what point of the match they were in.

“I wasn’t entirely sure what set we were in,” he said.

It has been a challenging year for Evans. He was one-and-done in the first three majors of the season and entered 4-17 this year in singles matches. Injuries had hampered him.

Tuesday was different. On Tuesday, he responded to adversity, none more so than in the final set, when he found himself in a huge hole. He rallied to win the next six games against Khachanov, a semifinalist at the 2022 US Open. Evans earned a second-round meeting with unseeded Argentinian Mariano Navone on Thursday.

“I think when you’re a kid, you’re just told to fight until the end,” said Evans, who reached the fourth round of the US Open in 2021 and the third round last year. “I mean, that’s sort of rule one. I’ve done that pretty consistently for my career. It sort of paid off a bit today.”

How much he will have left Thursday is uncertain. Evans won’t practice Wednesday. Instead, he will use the day to rest. Then, he will look to advance with some newfound confidence. He almost certainly won’t have to be on the court as long as he was Tuesday for his next match.

“I don’t really want to do that again,” Evans joked. “That’s for sure.”