"I feel really good. That's my best match of the tournament so far and I'm obviously happy to get the win on my birthday," Gauff told Sky Sports.

Both Gauff and Navarro are bidding to become the first American woman to win at Indian Wells since Serena Williams in 2001.

Gauff will play either 11th seed Daria Kasatkina of Russia or China's Yuan Yue in the semi-finals, while Navarro will face Greek ninth seed Maria Sakkari or France's Diane Parry.

Claiming the first break of the match in the eighth game, Navarro saved a break point before serving out the opening set, but Sabalenka fought back to win the second.

After exchanging breaks early in the decider, Navarro struck again for a 3-1 lead as Sabalenka's serve faltered and, after saving the first match point, the two-time major winner missed the second to hand Navarro the biggest win of her career.

The victory continues a strong season for the 22-year-old, who claimed her first WTA Tour title in January at the Hobart International.

"I'm feeling really good, it's never easy coming out and playing an opponent like that - so experienced and just so talented," Navarro said.

"She made it really tough on me today, but I was glad I was able to play some good tennis in the big moments."

In the men's draw, Norway's ninth seed Casper Ruud avoided a shock exit with a hard-fought win against French veteran Gael Monfils, who fell to a 3-6 7-6 (7-3) 6-4 defeat after two hours and 27 minutes.

Ruud will take on American 17th seed Tommy Paul or Italy's Luca Nardi in the quarter-finals.