Westminster's Desiree Sterling scored 16 points to go with nine rebounds as the No. 2 seed Titans defeated the No. 3 Presidents, 57-51, at Thomas More's Connor Convocation Center.
The loss ends the Presidents' streak of four consecutive appearances in the PAC title game.
Westminster (22-5) faces Thomas More, a 62-49 winner over Bethany, at 2 p.m. today.
Washington & Jefferson (19-8) held a 12-10 lead six minutes into the game before Nicole Fee scored four straight points to help Westminster take a 23-17 lead.
The margin at halftime stayed at six points at 30-24 after the teams exchanged baskets in the final minutes.
In the second half, the Presidents cut the gap to 30-28, but then hit a dry spell. They managed only three field goals over a 15-minute span. The Titans extended the lead to 51-34 during that time.
Washington & Jefferson didn't go down without a fight. The Presidents went on an 11-0 run to close the deficit to six points with under a minute to play, but the rally was too little, too late, and the Titans held on for the victory.
Fee finished with 12 points and Rachel Eaton added 11 for Westminster, which set a school record for wins in a season. Maria Hillenbrand and Emily Hays each scored 10 points to lead the Presidents, who have to hope for an at-large berth to the ECAC South Region Tournament. Kennan Killeen had nine points and five steals in the loss.