Swiss Indoors: Carlos Alcaraz returns to action, beats Jack Draper in thriller

Draper made the reigning US Open champion dig deep, winning the first set before going down to a 6-3 2-6 5-7 round of 32 defeat.

The deciding set saw 20-year-old Draper save three match points before Alcaraz finally prevailed after an enthralling contest that lasted two hours, 17 minutes.

The Spaniard was contesting only his second match since his US Open victory six weeks ago, after losing to David Goffin three weeks ago in the Astana opening round.

"In the beginning of the match it was tough," he told the ATP Tour website. "I did a lot of mistakes in the beginning.

"I wanted to play really aggressive on this court. For me, it's a bit slower than the other tournaments. But obviously I had to handle that, I had to work on my problems and change my tactics a little bit in the second set.

"I knew that Jack is playing great. He is a really dangerous player and I really had to be focused and, of course, never give up."

Alcaraz finished with 39 winners and 34 unforced errors, compared to 27 and 12 from Draper.

He moves on to face either Botic van de Zandschulp or Adrian Mannarino in the second round.

Also advancing on Monday in Basel were Brandon Nakashima and Alexander Bublik.

Nakashima came from a set down to defeat David Goffin 2-6, 7-6(4), 6-4, while Bublik downed Aslan Karatsev 6-3, 7-6(2).