Four Washington starters scored in double figures, the Seattle Storm were outrebounded 44-28 and the host Mystics claimed a 69-58 victory on Saturday night.
Shakira Austin had 14 points and 11 rebounds, Sug Sutton scored 13, and Brittney Sykes and Sonia Citron notched 11 points each for the Mystics.
Storm All-Star guard Skylar Diggins continued a recent stretch of spotty scoring. She shot 2-for-10 and tallied five points, her third time shooting below 30 percent and scoring less than her season average (17.7) in the last four games.
Seattle started the fourth quarter with an 11-0 run, including six from rookie Dominique Malonga. Washington's Kiki Iriafen ended the streak and scored the team's first fourth-quarter point at the free-throw line with 4:03 remaining.
After Seattle drew within five, Mystics leading scorer Sykes responded with consecutive layups to make it 67-58 with 51 seconds left, and Washington held on from there.
Seattle forward Nneka Ogwumike was held scoreless in the second half and finished with 18 points.
The Mystics dominated the middle two quarters, outscoring the Storm 44-24 in the two frames.
Washington outscored Seattle 24-14 overall in the second frame. Ogwumike cooled off in the second, notching only four points and shooting zero free throws, down from the five she attempted and made in the first.
Citron notched nine points in the first half and surpassed her scoring output in the past two games. She shot a combined 5-for-16 from the field in those contests.
The Mystics extended their lead in the third quarter while the Storm couldn't buy a basket.
An Austin layup with 1:36 left in the frame grew Washington's lead to 58-39. Seattle totaled only 10 points in the quarter and shot 3-for-17 from the field, while the Mystics outrebounded them 13-5.
Seattle sank two quick baskets in the fourth quarter to cut the deficit to 60-49 and force a Washington timeout at the 8:56 mark.
Much like the first matchup between these teams, the Mystics played hounding defense to open the game. Washington didn't allow clean possessions for much of the first quarter, but Ogwumike still converted on tough shots and drew fouls.
Ogwumike took over the game early on, scoring 14 of the Storm's 21 first-quarter points and giving Seattle a five-point lead after the first frame.
Washington was sluggish to begin the game, shooting 7-for-22 from the field (31.8 percent) and 1 of 7 from three (14.3 percent).
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