WASHINGTON (AP) -- Plenette Pierson scored 20 points to help the New York Liberty snap a three-game losing streak and hamper the Washington Mystics' playoff seeding with a 73-61 victory Saturday night. Ivory Latta scored 15 points for the Mystics (16-18), who needed a victory in its season finale plus additional help for a chance at getting the No. 2 seed in the Eastern Conference and home-court advantage in the opening round. However, Washington's loss and Indiana's 71-67 win over Chicago clinched the second seed for the Fever. The Mystics can drop to No. 4 if the Sky beat San Antonio in their season finale on Sunday. ''This game is behind us,'' Latta said. ''Clean slate, 0-0 going into the playoffs. We've got to be focused and ready.'' Washington will open the playoffs against either Indiana or top-seeded Atlanta. The Liberty (14-19) did not commit a turnover in the first half, led by 16 at halftime and 60-40 in the third quarter. New York shot 51 percent from the field and never let its lead dip below 11 points in the second half. ''We executed our offense,'' New York coach Bill Laimbeer said. ''This was about as good as we've executed in a while.'' Mystics coach Mike Thibault could not say the same about his squad, which has lost three of the last four games. Washington, which won 11 games combined from 2011-12, clinched a playoff berth for the second straight season with Friday's win at Connecticut. The team flew home Saturday morning and then played like a jetlagged squad in the first half, committing 11 of its 19 turnovers. ''It's disappointing to end your home season like that,'' Thibault said. ''I don't know if we were flat from last night, but we were bad in the first half. They did whatever they wanted pretty much.'' Pierson made all six of her field-goal attempts for 16 points before halftime. New York outscored Washington 26-12 in the second quarter. Swin Cash added 12 points for the Liberty. Though outrebounded 39-24, including 16-1 on the offensive boards, New York held Washington to 36.1 percent shooting from the field. Tianna Hawkins scored 11 points for the Mystics. Washington split the season series 2-2 with Indiana and lost three of four to Atlanta. The Mystics fell to the Dream 2-1 in the opening round of the 2013 playoffs. ''Unless something crazy happens we'll probably play Atlanta,'' Thibault stated, expecting Chicago to win its finale. ''They have a lot of experience. They (were in) the Finals last year. ...They have way more experienced players than us, but we've shown we can play with them.''