Ben Shelton beaming as he wins maiden ATP Tour title at Japan Open

The 21-year-old only turned professional just over a year ago but has made rapid strides, reaching the US Open semi-finals last month, and he will become the fourth American in the top 15 of the rankings on Monday.

Shelton showed no nerves during the final against Karatsev, and it was the Russian who smashed his racket in frustration during the second set as his opponent eased to a 7-5 6-1 victory.

"That meant a lot to me and my team," said Shelton on atptour.com. "We have been working really hard since the beginning to build my game and win titles on the ATP Tour.

"I made some deep runs lately. You see the great champions, they finish weeks off. They win titles, they don’t just get to finals. They are able to maintain their level throughout the week.

"I am not saying I am anywhere there yet but to be able to do it for one week, put together five matches in a row in Tokyo, is really special."

Shelton, who could yet make a charge to qualify for the ATP Finals next month, is coached by his father Bryan, and the pair become the fourth father-son duo to win tour-level singles titles in the open era.

At the other end of the scale, Gael Monfils beat Pavel Kotov 4-6 7-6(6) 6-3 in the final of the BNP Paribas Nordic Open to become only the fourth player older than 37 to win an ATP Tour title.

Veteran Monfils had to dig deep in Stockholm to down the qualifier after a battle that lasted two hours and 35 minutes.

Monfils, who follows in the footsteps of Roger Federer, Ivo Karlovic and Feliciano Lopez in winning an ATP Tour title aged 37 or older, said: "I ran a lot today.

"When I had to save break points in the second set, I tried to push through. I don’t know how I pulled up but I kept believing and fighting."

French teenager Arthur Fils was unable to join his compatriot Monfils in the winners' corner after he lost to Alexander Bublik in the European Open final.

Fils had stunned Stefanos Tsitsipas on Saturday to make the showpiece in Antwerp, but came unstuck against tricky Kazakhstan opponent Bublik by a 6-4 6-4 score.

Third seed Bublik sent down 11 aces to clinch the title.

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