Nadia Petrova defeated world No. 3 Agnieszka Radwanska on Saturday to win the $2 million Japan Open, the biggest title of her career.

Petrova took the first set at a canter, lost the second just as easily, but recovered in the decider for a 6-0, 1-6, 6-3, win on the hard court in Tokyo.

The closest the 30-year-old Russian has come to clinching the lion's share of such a big purse was in 2006, when she won three $1.3 million events.

"I played great in the first set but may have used too much energy, and in the second set I felt flat," Petrova said on the WTA website.

"It took me a while to recuperate and get back into the game. After the second set when I went to change my clothes, I had a few minutes to think about what to focus on in the third set."

It was Petrova’s 12th WTA title and second this year after taking the $220,000 UNICEF Open in the Netherlands by beating Radwanska's younger sister Urszula in the final.

Petrova has a career ranking high is No. 3 in 2005, when she reached the French Open semifinal and the quarterfinals of Wimbledon and the U.S. Open.