No.9 seed Alina Korneeva triumphed in a grueling final between 15-year-olds to win the Australian Open junior girls' singles title, overcoming No.7 seed Mirra Andreeva 6-7(2), 6-4, 7-5 on Rod Laver Arena on Saturday.

Playing in the first junior Grand Slam tournament of her career, Korneeva prevailed over her friend and doubles partner after 3 hours and 18 minutes of back-and-forth play. Korneeva and Andreeva teamed up to reach the junior girls' doubles semifinals this week as well.

"It's my first Grand Slam and I hope not the last one," Korneeva said in her victory press conference. 

"I'm so proud of myself, of my mental game," the champion added.

In the evenly-matched encounter, Korneeva won 139 points to Andreeva's 138. Andreeva had six more winners but 15 more unforced errors than Korneeva, and Korneeva had eight service breaks compared to six for Andreeva.

"I think we can say that [Andreeva and I] are the best friends off the court," Korneeva said. "On the court, of course I can't give to her the points. We are the opponents on the courts.

"Off the court, we are the best friends. I love her so much. She's my girl, I don't know, my person that I can say everything to her. I hope we will have a good relationship together.

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"[Andreeva is a] very good player, and I hope, I know that we will have a lot of good matches in the future. I know that sometimes she will win. It's normal, it's life. I said to her that, 'Don't cry, Mirra, because it was a very good match, very tough battle, a lot of good points.'"

Lengthy all-court rallies made routine appearances during the match, with Andreeva prevailing in the first-set tiebreak before Korneeva countered by taking the second set. The match was already 2 hours and 18 minutes old before the pair started the third set.

Korneeva took a 4-1 lead in the decider, but Andreeva pulled all the way back level at 4-4. Back-to-back double faults by Andreeva allowed Korneeva to break again for 5-4, but Andreeva saved two championship points and won a 10-minute game to reach parity once more at 5-5.

Korneeva, though, broke Andreeva for an eighth time to garner another opportunity to serve for the match, and she took advantage of that second chance, serving out the final at love.

The girls' doubles final was contested on Saturday, and it too went down to the wire. Unseeded Renata Jamrichova and Federica Urgesi overcame No.4 seeds Hayu Kinoshita and Sara Saito 7-6(5), 1-6, [10-7] in 1 hour and 18 minutes to clinch the Australian Open title.