Emma Raducanu and fellow Briton Jack Draper both won on Saturday to reach the third round at Indian Wells.
She will now face either Beatriz Haddad Maia of Brazil, who is the 13th seed, or the Czech Republic's Katerina Siniakova.
Draper, the world number 56, beat compatriot Dan Evans 6-4 6-2.
Raducanu, 20, continued her return to form after shrugging off illness and a recurring wrist injury to beat Danka Kovinic on Thursday.
The world number 77 fought back to win the opening set on a tie-break, then eased through the second set.