The Royals lost only 6 games all match en route to an 18-0 win over Ventura in the first round of the CIF-Southern Section Division 1 tournament on Thursday.
San Marcos plays Saturday against La Canada, which beat Valencia, in the second round.
Giulio Rambelli went 3-0 at No. 3 singles, winning each set 6-1.
“Giulio moved well in the toughest conditions of the year,” Royals coach Jarrod Bradley said. “The wind was relentless, but he did an excellent job getting to the ball quickly and hitting smart shots with the wind and into the wind.”
San Marcos is now 14-0 on the year.