MOSCOW, Russia - No.2 seed Kiki Bertens scored a dramatic victory over Kaia Kanepi in her opening match at the VTB Kremlin Cup, and kept her hopes of qualifying for the Shiseido WTA Finals Shenzhen in the season's final days alive.

The World No.8 needs to make the final in Moscow to secure qualification for the year-end championships, and battled back from a break down in the second and third sets against the always-dangerous former World No.15 to seal a 4-6, 6-3, 7-5 victory in two hours and 18 minutes.

"It was a tough match. I was struggling a little bit with how my body was feeling, and Kaia is a great player," Bertens said after the match. 

"She was playing really great, really aggressive and it was tough to beat her. I was just really pleased that I was fighting for each point and I got there in the end."

Trailing 3-1 in the second set, Bertens won five games in a row, and also came from 4-1 down in the final set to advance to the quarterfinals, where she will face France's Kristina Mladenovic.

Kanepi, in action at WTA level for the first time since the US Open this week, came from a break down in the first set herself to take a one-set lead in pursuit of her first Top 10 victory of the season.

Though she hit just 10 winners to 19 unforced errors in the opener, Kanepi's efficiency on break points helped her seal the early advantage: the former World No.15 went 3-for-4 on break point chances, and saved three of the five she faced, across the first set. 

From 4-4 in the opener, Kanepi won five straight games to take command in her first match against Bertens in seven years, and the 34-year-old Estonian later quickly shook off the disappointment of letting her second-set lead slip away. 

She saved two break points to start the decider and won four of the first five games, but the Dutch No.1 had other ideas from then on as she pursued the comeback. 

"It was tough because I was also 1-4 down in the third set, and a break in the second, but I just kept fighting for it," Bertens said. "When I broke her, I was like, 'Okay, just try to move now, try to hold now, and put your best effort.'" 

Bertens owns a 1-0 head-to-head record against Mladenovic, who beat No.6 seed Anastasija Sevastova in three sets in other second round action on Thursday.

Should Bertens win that match, and No.3 seed Belinda Bencic beat qualifier Kirsten Flipkens on Friday, the duo will face off in a winner-take-all semifinal that will send the victor to the WTA Finals. 

"To be honest, I'm not really feeling the pressure. Whoever plays the best is going to Shenzhen and I hope that I can be a part of it," Bertens said.

"Last year was great playing in Singapore, and of course I want to be there in the first edition in Shenzhen, but I'm having a great year. The best players deserve to be there, so let's see after this week."