Daria Kasatkina defeated Russian compatriot Mirra Andreeva 6-0, 4-6, 6-4 to win the Ningbo Open final in China on Sunday and her second title of the season.
Eastbourne champion Kasatkina, who has lost four finals this year, breezed through the opening set as the 17-year-old Andreeva looked nervous.
After winning the opening game of the next set, Kasatkina faltered, and her close friend Andreeva rallied to draw level when the world No. 11 sent a backhand wide.
Andreeva built a 3-0 lead in the deciding set, but the momentum swung Kasatkina's way again as Andreeva's unforced error count climbed rapidly.
Kasatkina, 27, secured the eighth trophy of her career and will break into the world's top 10 on Monday.
"In the first set, I gave everything. I was super focused, and the level was so high," Kasatkina told reporters. "But obviously after that, I dropped a little bit and Mirra was there ready to take it over. She's this kind of player who never gives up, and to win any point you have to almost die on court.
"I feel like I did a miracle in the third set because it was a very tough moment. I was not very far from losing belief. ... In tennis the top 10 is a very important achievement."
Andreeva was in tears after missing a golden chance to claim her second title this year after her triumph in Iasi, Romania.