Washington tallied 27 fourth-quarter points and overcame a poor shooting night from distance to knock off Seattle 74-69, climbing over the .500 mark for the first time since May.
Led by rookie All-Star Kiki Iriafen, Shakira Austin and leading scorer Brittney Sykes (17.5 points per game), Washington held down the paint. The Mystics outrebounded the Storm 36-29 and outscored them 48-30 in the paint to claim their third win in a row, matching a season-high.
Ezi Magbegor led Seattle with a season-high 19 points.
The Mystics entered the fourth quarter down by 10 before outscoring Seattle 27-14 in the final frame.
Washington's second rookie All-Star, Sonia Citron, went on a personal 5-0 run to help snatch the lead from Seattle and take a 62-61 advantage with 4:28 left in the game. She finished the game with 17 points.
Sykes, who tallied a team-best 19 points, converted a layup to put Washington up by three with about 20 seconds left. Facing a 72-69 deficit, Skylar Diggins caught a pass in the corner, but narrowly stepped out of bounds and turned it over to effectively seal the game.
Diggins, who leads Seattle in points and assists per game, had a quiet shooting night, going 4-for-14 from the field and scoring only 10 points.
The third frame swung the game in Seattle's favor, as it outscored Washington 27-16 and took an eight-point lead.
Washington's offense looked anemic for most of the third quarter. After Stefanie Dolson made a three at the 9:28 mark, the Mystics didn't convert another field goal for almost eight minutes. They notched only four paint points in the quarter, and their shooting remained cold.
The visitors misfired on 11-of-14 shots from behind the arc for the contest.
In the first quarter, Washington's defensive tenacity seemed to roll over from their 70-68 win over the Las Vegas Aces on Thursday. Seattle started the game 3-for-18 from the field, with two of their made attempts being 3-pointers from forward Nneka Ogwumike.
Still, the Storm only found themselves down 16-10 after one quarter.
Seattle's offense shook off the slow start in the second quarter, taking a 22-20 lead on a Gabby Williams layup at the 6:41 mark. Despite poor shooting, the Mystics rallied and led 31-28 at halftime Washington went 0-for-7 from three and 5-for-11 on free throws in the first half.
Both teams struggled with turnovers in the first half, committing eight each.
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