Defending champion Caroline Wozniacki has upset new world No.1 Garbine Muguruza 6-2 6-0 to advance to the final of the Pan Pacific Open in Tokyo.

Wozniacki, the 2010 and 2016 champion, converted six of seven break points on Saturday against the Spaniard to reach her seventh final of the year.

Playing in her first tournament since earning the WTA’s top ranking, Wimbledon champion Muguruza had 29 unforced errors to drop the final 10 games of the match.

Denmark’s Wozniacki will face Anastasia Pavlyuchenkova in Sunday’s final. The Russian rallied from being down 3-0 in the final set to beat former world No.1 Angelique Kerber 6-0 6-7 (4-7) 6-4.

Pavlyuchenkova, aiming for her third title of 2017, broke serve seven times and won six of the final seven games.

She withstood a furious fightback from Kerber after the match appeared headed for a blowout. The 26-year-old took the first eight games.

However, Kerber dug in and broke Pavlyuchenkova’s serve in the third game of the second set, before the 29-year-old German forced a tiebreaker and stole the second set.

A rattled Pavlyuchenkova dropped the first three games of the final set but regained her composure to win six of the final seven.

“It was a lot of drama,” a relieved Pavlyuchenkova said in a courtside interview. “I actually didn’t expect I would start so good today and I was playing really good tennis.”

Going into the match, Kerber held a 5-4 edge in career meetings but Pavlyuchenkova had won their most-recent clash, the final of the Monterrey Open in May.

“It’s never easy with her,” Pavlyuchenkova said. “It was a great match. I’m really happy to be in the final.”

Kerber said she struggled to find her feet at the start of the match.

“In the first set, I was completely not in my rhythm, not in my game, and she started very well.

“I tried to turn it around and I won the second set. So in the end, it was still a good match.”