El Tawil defeated Margarita Treyes of host San Francisco 6-0, 6-4 in round of 16 singles action on Friday, the opening day of the six-team, 16-player event at the California Tennis Club.
A senior, El Tawil led off the day by teaming with Katya Tabachnik in doubles, but the duo was upended 8-7(6) in a quarterfinal matchup with Alexa Corcoleotes and Madison Westby of USC.
Tabachnik, playing in her first collegiate tournament, fell to Tamara Culibrk of San Jose State 6-4, 6-4 in round of 16 singles.
Tabachnik rebounded in the consolation bracket, downing Shanna Dos Santos of San Francisco who was forced to retire after dropping the opening set 6-2.
El Tawil will face Emma Wilson of Fresno State at 1 p.m. Saturday in the quarterfinals. Tabachnik received a bye in the consolation quarterfinals and will play Juliane Triebe of Fresno State at 1:30 p.m. Saturday in the semis.
The three-day event, which also features players from Pacific, concludes Sunday.