The 14-year-old from Melbourne held off a spirited charge from second seed Indiya McLeod to clinch her first Albury title, 6-3, 7-6.

Players were thrown a curveball on Tuesday morning as a major downpour flooded the grass courts and forced all matches to be moved to synthetic.

It was the third surface change in the space of four days as matches were transferred to hardcourts and synthetic on Saturday, before a switch to grass on Sunday and Monday, with the final back on synthetic.

Mihulka was impressive on serve to close out the first set, but McLeod didn't go away in the second.

The Sydneysider continued to make Mihulka play an extra ball and forced errors at key stages to keep her hopes alive.

Five consecutive breaks of serve at the end of the second set forced a tiebreak, but Mihulka claimed the first point and never handed back the advantage as she eventually secured it 7-4 to claim the title.

"It's pretty exciting to be the youngest winner," Mihulka said.

"I thought I played pretty well and was able to fight through, especially at the end.

"Indiya is a really great player and she made me hit a lot of balls, so it was really tough.

"It was the first time I had played her but I felt like I stuck to my game, I was aggressive and tried to move forward.

"I was a bit bummed when it started to rain in the morning because I really wanted to get on, so it was good that it stopped and everything cleared up."

Mihulka said she was able to adapt well to matches on different surfaces.

"The grass was really good. I would have preferred to play the final on the grass," she added.

Mihulka next heads to Singapore to play in two International Tennis Federation tournaments.

"I've been playing a lot of open events and have been really enjoying the challenge," she said.

"It will be my first time playing in Singapore."