At Thomaston, Rachel Frye pitched a one-hitter with nine strikeouts and a walk to help the top-seeded Mariners move into the semifinals.
Molly Mellor belted a home run and a single with two RBIs to spark Oceanside (16-1). Hannah Hersom singled twice and Jessie Veilleux hit an RBI double.
Brittany Rollins spaced five hits with nine strikeouts and three walks for 10-7 Gardiner, the No. 8 seed.
Gardiner (10-7) 000 000 0 — 0 1 0
Oceanside(16-1) 000 301 x — 4 5 4
Rollins and Plourde; Frye and Veilleux