TOKYO, Japan - From a break down in the final set, unseeded Italian Camilia Giorgi scored her ninth career victory over a Top 10 player against top seed and two-time defending champion Caroline Wozniacki to reach the quarterfinals at the Toray Pan Pacific Open.

Trailing 0-2 in the final set, the World No.37 ran off six of the last eight games to score her best win in terms of ranking, and first win over a Top 10 opponent she defeated then-World No.5 Elina Svitolina on the grass courts of Birmingham last season, 6-2, 2-6, 6-4.

It is also her first Top 10 win on hard courts since the Katowice Open in 2015, where she defeated then-World No.9 Agnieszka Radwanska, and all three of her career wins against the former World No.1 have come on the surface.

"It was a very good match," Giorgi said after the match. "This is a nice court and [today] was very fun. I was very consistent today, and consistent mentally, so this was important."

Giorgi started the match with a flourish, breaking the top seed twice in the first five games to assert her authority early in the opener.

The Italian hammered a staggering 16 winners over eight games in the first set, four times Wozniacki's total of four, and misfired only eight times to take a one-set lead in 38 minutes. 

Contesting her first match since a surprising second-round exit to Lesia Tsurenko at the US Open, Wozniacki was not yet ready to see her quest for a third straight title in the Japanese capital end easily.

The Dane saved all nine break points she faced in the second set - including one in the first game and five at 1-1 - to send the match the distance, as she broke Giorgi twice, despite seeing the Italian land 70 percent of her first serves.

"I didn't make so many mistakes on serve, but in the second set, I started missing and having some problems with tactics," Giorgi said. "But it was a very good third set."

In the decider, it was Wozniacki who started the quicker of the two, winning eight of the first nine points to build a 2-0 lead.

However, Giorgi again found her range off the ground, as she broke Wozniacki from 30-0 down in the ensuing game to get back on serve, and struck again to take the lead for good in the seventh game. 

Over the course of two hours and five minutes, Giorgi struck 45 winners to just 29 unforced errors, while Wozniacki totaled 14 winners to 17 unforced. The Italian's bold play afforded her 16 break point opportunities in the match, but she needed only four to earn the win.

Up next for the Italian in her fifth quarterfinal of the season will be another Australian Open champion in Victoria Azarenka, who scored her first Top 20 victory in six months earlier on Thursday over Ashleigh Barty.

On the two-time major-winner and former World No.1, Giorgi said: "I'll just focus on my game, like always, and I'll hope to play like this - very consistent."