The 22-year-old, playing in his second competition since reaching the US Open semi-finals, won 6-4 7-5 against the Russian world number 24 in Vienna.

Draper looked set to breeze to victory after going 4-0 up in the second set but was then forced to dig in when Khachanov threatened a comeback by winning the next five games in a row.

The seventh seed became the fourth British player to triumph at the tournament, following in the footsteps of Greg Rusedski, Tim Henman and two-time winner Andy Murray.

“I was playing so good and then the momentum shifted a little bit,” Draper told Sky Sports.

“Honestly, I didn’t feel like I was too nervous or too tight; I just missed a few balls here and there, maybe [made] a couple of wrong decisions and Karen started swinging, he started picking up his level.

“That’s a testament to how good he is, he’s a fighter, obviously on great form.

“It got really tight there for a minute, but I stayed solid, I stayed mentally in a good frame, and luckily I was able to come through when it mattered. But, yeah, it’s a relief.”

Having already guaranteed a top-15 ranking with his performances this week, Stuttgart Open champion Draper described the match as his “biggest final yet.”

He wasted little time in asserting his authority on the contest as his stellar breakthrough season continued with a devastating first-set display.

Opponent Khachanov, who beat second seed Alex De Minaur and 2021 Wimbledon runner-up Matteo Berrettini en route to Sunday’s showpiece, was broken from 40-15 up in game three.

That proved to be the decisive moment in an opening set which was wrapped up in 40 minutes after Draper served strongly and produced an array of eye-catching winners.

Khachanov had also been serving well but showed signs of nerves when he was twice broken to love at the start of the second set to fall 4-0 behind.

The match appeared to have slipped away from the 28-year-old, but he gave Draper plenty to ponder by impressively moving 5-4 ahead during a substantial momentum shift.

However, the Briton regained his composure at a crucial moment to secure his first ATP 500 title thanks to a gruelling victory in an hour and 35 minutes.

“There are so many amazing players in this draw and to win my first ATP 500 feels incredible,” added Draper.

“I’m incredibly happy, I’m so proud of myself and my team and all the work we put in — it’s for moments like this, so I’m going to enjoy it.”