The No. 7-seeded Beyer High girls water polo team was upset in the opening round of the Sac-Joaquin Section Division II Tournament, falling to Merced 9-7.
The Patriots were one of numerous Stanislaus District girls teams to play first-round games on Tuesday.
With the victory, No. 10 Merced will play Thursday at No. 2 El Capitan, which had a first-round bye.
In other Division II action, Buhach Colony defeated Johansen 18-5. The Thunder advance to the second round, where it will meet No. 1 Rio Americano, which had a first-round bye.
In a Division I game, sixth-seeded Turlock handed River City a 17-8 defeat. The Bulldogs will next face No. 3 Granite Bay, which defeated No. 14 Pitman 12-1 on Tuesday. No. 13 Gregori plays Wednesday at No. 4 Woodcreek.
The girls tournament will continue at home sites on Thursday, where the winners will advance to the semifinals on Tuesday at Johansen High.
Among those playing Thursday are No. 1 Sonora and No. 2 Ripon in the opening round of the Division III tournament. Sonora plays El Camino, while the Indians host Amador,
The boys tournament gets under way on Wednesday.