Solid defense to start and finish the game earned a nine-point win for the host Panthers.
Megan Sharp led the way for Washougal with 18 points, and made four free throws down the stretch to help seal the victory.
The Panthers (11-9, 4-4), who finished third in the Class 2A Greater St. Helens League, will travel to River Ridge of Lacey on Friday to open the district tournament. Washougal had a shot to share second place in the league, but Hockinson secured second place with a win at Ridgefield, avoiding a Wednesday game to break a tie.
Six 3-point field goals helped the Panthers overcome 9-for-20 foul shooting against R.A. Long (10-10, 2-6). And Washougal held the visitors to six points in the first quarter and to four points in the fourth.