Anastasia Potapova beats Ons Jabeur, her mom's favorite player, in San Diego

WATCH: Anastasia Potapova knocked out top seed Ons Jabeur in the second round in San Diego.

The old saying goes that mother knows best. But, in the case of Anstasia Potapova, does she?

The 22-year-old rising star notched her fourth Top 10 win of the season on Wednesday in San Diego with a 6-4, 7-6(4) victory over No.1 seed Ons Jabeur in the second round of the Cymbiotika San Diego Open.

Jabeur was the crowd favorite over the course of the one-hour, 46-minute clash, as fans at the Barnes Tennis Center tried to will the three-time Grand Slam finalist back into the match. Jabeur served for the second set twice, at 5-4 and 6-5, and clawed back from 4-0 to 4-4 in the tiebreak, but ultimately couldn't force a third set.

But, as Potapova revealed in victory, they weren't the only people in her orbit who were rooting for the affable Tunisian.

“My mother, she loves [Jabeur] so much," Potapova said in her on-court interview. "Every time I talk to my mom on FaceTime, if Ons is around, she’s like, 'Call Ons! She’s my best player!' They’re actually pretty good friends. I don’t know if she’s happy that I won today.

"It's either she's the happiest, or she's a little bit sad. I'll check later!"

The two players shared a hug of their own at the net when the match was over, and Potapova credited her patience and focus as keys to getting her over the line in the end.

"Ons is very tough to play. She's truly one of the best in the world, and her style makes it very uncomfortable," she said. "But I'm really happy and proud to get this win."

Having also beaten American Alycia Parks in three sets in Round 1, Potapova earned back-to-back wins for the first time since Wimbledon with her upset of Jabeur. For a spot in the semifinals, Potapova will face 2020 Australian Open champion Sofia Kenin.