Marta Kostyuk has won her first career WTA title at age 20 by beating Russia's Varvara Gracheva 6-3 7-5 in the ATX Open final in Texas, then dedicated the victory to her home country of Ukraine.

Eighth-seeded Kostyuk and unseeded Gracheva did not meet at the net for the traditional post-match handshake; Kostyuk has said she will not do so after facing any opponents from Russia, which began its invasion of Ukraine more than a year ago, or Belarus, which helped launch the attack.

"Being in the position that I am in right now, it's extremely special to win this title," Kostyuk said during Sunday's trophy ceremony in Austin.

"And I want to dedicate this title to Ukraine and to all the people that are fighting and dying right now."

When world No.88 Gracheva sailed a forehand long to end the match, Kostyuk - who trailed 5-3 in the second set and saved a set point at 5-4 - dropped to her knees at the baseline, put her hands on her face and sobbed.

"Obviously," said Kostyuk, who was the junior champion at the 2017 Australian Open, "it's a very special moment."

Both players were participating in a tour-level title match for the first time, and they combined for 13 breaks of serve - eight by Kostyuk - and 14 double-faults. Both won fewer than 50 per cent of points on serve.

Kostyuk, who came into the day ranked 52nd, became the third first-time champion on the women's tour in 2023.