Kara Schoenherr scored 20 points to lead Rainier to the 1A District 4 playoff win.
Ridgefield finished the season with nine wins and 12 losses.
Shannon Boyle scored 19 points for the Spudders, including eight in the first quarter which ended with Ridgefield holding a 10-9 lead.
Rainier led by eight at halftime, then put away the game in the third quarter.
Ridgefield coach Carl Click said Rainier’s work on the offensive boards was the difference in the game. He said Schoenherr was especially effective scoring second-chance points.
RAINIER 48, RIDGEFIELD 35
RIDGEFIELD (9-12) — Cami Pickett 3, Carly Estes 5, Beatrice Bremer 2, Brooke Kates 2, Emily Burton 0, Shannon Boyle 19, Elizabeth Vance 2, Rachael Thomas, Kayla Weaver 0, Jessica Shaffer 2. Totals 14 (1) 6-12 35.