Playing a second straight qualifier, Sabalenka did not have it all her way early in the opening set on Rod Laver Arena and swapped breaks with her opponent after some wayward hitting.

"I think for someone who is 16, she's doing an incredible job," Sabalenka said. "I wish I was at that level at that age. She's an unbelievable player, if she keeps on working she'll be at the top real soon.

"I'm super happy with the win. I was focused on myself, not on anything else and I just tried to fight for every point."

Sabalenka quickly reset to find her range for a 5-3 lead following a second break of serve before she wrapped up the first set and surged to a 4-0 lead in the second.

World number 107 Fruhvirtova responded to get on the board but Sabalenka was in no mood to allow an unlikely comeback and reeled off the winners en route to victory.

The Belarusian will next play either Ukrainian 28th seed Lesia Tsurenko or Spain's Rebeka Masarova.