Katerina Siniakova stuns Caroline Wozniacki to win the Swedish Open

Siniakova is ranked 50 places below her top-seeded opponent, the world number six, but stormed to a 6-3 6-4 victory in Bastad.

Injury may have played a part as both players took medical time-outs on the red clay but Siniakova held firm to enhance her reputation as one of the most promising players in the women's game.

The 21-year-old adds to her maiden success in Shenzhen earlier this year and is set to climb to world number 39 on Monday.

"It's really amazing for me," Siniakova said during the trophy presentation. "Last year was really good, and so I'm so happy that I came back because I couldn't imagine a better week.

"Caroline has had such a great season and it's so much pressure to play against you. I'm sorry I won. I was just enjoying the game even in the tough conditions."

Wozniacki has enjoyed a recent resurgence and the Dane will be optimistic about her chances at the US Open next month, where she made the semi-finals last year.

This, however, was her fifth final defeat of 2017, following runner-up finishes at Doha, Dubai, Miami and Eastbourne, and she was unusually erratic with 39 unforced errors.

"I'm looking forward to the US Open Series and the US Open," Wozniacki said.

"It's one of the tournaments where I've done my best and it's one of my favourite tournaments of the year.

"I'm excited to go back, see how I can do on the hard courts and hopefully finish the year strongly."

Elsewhere, China's Peng Shuai eased past Japan's Nao Hibino 6-3 6-2 to win the Jiangxi Open in Nanchang.

Peng won her first WTA title, also on home soil, at the Tianjin Open last year and secured her second with a comfortable victory in one hour and 27 minutes.