Daria Kasatkina fought past her good friend Mirra Andreeva to win the Ningbo Open title in China.
Russian fifth seed Kasatkina beat her teenage compatriot 6-0 4-6 6-4 in a scrappy encounter.
Andreeva broke down in tears after the match, having squandered a 3-0 lead in the final set.
However, she was quickly comforted by Kasatkina, before joking: “I really tried not to cry because I knew the pictures would be ugly but I just couldn’t help myself, I’m sorry guys.”
World number 11 Kasatkina looked to be cruising after making just two unforced errors in a dominant opening set.
Andreeva, 17, produced a stirring comeback and looked in control after winning the first three games of the deciding set.
But Kasatkina capitalised on a series of unforced errors, winning five games in a row before serving out victory.
Andreeva, who reached the semi-finals of the French Open this year and claimed doubles silver at the Olympic Games in Paris, had been bidding for a second career singles title.
Kasatkina, meanwhile, had lost four singles finals this year – with Andreeva jokingly congratulating her for “finally closing one out”.
“Thanks for reminding me that I lost so many finals this year,” Kasatkina said afterwards.
And she added: “Congratulations on the final, I saw you crying but you are going to make a lot of them. I hope we will share some more of them in the future.”
It is a second title of the year for Kasatkina after winning Eastbourne in June and the eighth singles triumph of her career.
At the Nordic Open in Stockholm, Great Britain’s Harry Patten claimed a fourth men’s doubles title in his first year with new partner Harri Heliovaara, of Finland.
The top seeds saw off Czech pair Petr Nouza and Patrik Rikl 7-5 6-3 in Sunday’s final.