San Marcos scored first on Tuesday at Buena but ultimately settled for a 5-2 loss to the Bulldogs.
It was the Channel League opener for the Bulldogs while San Marcos won their opener last week.
Buena led 3-2 at halftime and built on its lead in the second half.
Royals head coach Macie Berlin said her team played hard throughout.
“We were working hard, but losing control of our shape and our cohesiveness. To be honest, Buena baited us to play slowly before attacking and we fell for it throughout the first half,” Berlin reported.
“It was back and forth the second half but it never was the unit that I know we can be.”
San Marcos’ first goal started with keeper Emily Stevens, who gave it to Natalie Widmer, and then up top to Kaitlyn Saperstein. Chloe Hamer took a pass from Saperstein and beat Buena’s keeper.
Olivia Jones scored San Marcos’ second goal on a pass from Raynee Odell in the 33rd minute.
Buena’s final two goals came in the last 10 minutes.
“Games like this are always a tough loss, and I always imagine having a season without them, but they are also the best lessons and the reason why we play two league rounds,” Berlin said.
San Marcos’ next match is next Thursday against Dos Pueblos.