The Dane beat her American opponent, the oldest woman to reach the final at 37, 6-4, 6-4 to finish the year as world No 3. “Going into the tournament you know that it’s going to be a tough one,” said Wozniacki.
“I’m really proud of how I have played all week and how I have fought and how I really produced some great fighting out there. To be here with the trophy means a lot, and it’s a great way to finish off the year.
“I was hoping that if I’m going to beat her [Williams] at least once in my career it had to be today. I just went out there and I just did my best.” Former world No 1 Wozniacki looked to be on course for a comfortable win at 5-0 in the second set only for Williams to rally and take the next four games. But the Dane broke her opponent’s serve to secure her second title of the year after winning last month’s Pan-Pacific Open in Tokyo.
In Basel, Roger Federer recovered from a set down to beat Juan Martin del Potro and win the Swiss Indoors title for a record eighth time.
Del Potro took the opening set on a tie-break and broke in the first game of the decider, only for Federer to come roaring back to win 6-7 (5/7), 6-4, 6-3.
The 36-year-old’s seventh title of the year is also the 95th of his incredible career and takes him to within 1,460 points of Rafael Nadal in the battle to end the year ranked No 1 in the world.
Federer broke Del Potro’s serve in the first game of the match and again in the ninth, but was unable to serve out the set and also squandered a 3-0 lead in the tie-break.
Del Potro rattled off six points in a row and although Federer saved two set points on his own serve, a service winner from Del Potro gave him the set after 65 minutes. A solitary break of serve in the tenth game of the second set was enough for Federer to force a decider, which he started by losing serve and hammering a ball into the roof of the arena in frustration. But that seemed to fire up the 19-time grand-slam champion, who took the next four games in succession before serving out for victory.
In Vienna, Lucas Pouille claimed the biggest win of his career by beating Jo-Wilfried Tsonga 6-1, 6-4 in the final of the Erste Bank Open.
Pouille’s maiden ATP World Tour 500-level victory makes him the first player in 2017 to win on all surfaces, adding a hard-court crown to triumphs on the clay of Budapest and grass of Stuttgart.