Williams and Thomas made back-to-back jumpers to open overtime and give Connecticut its biggest lead of the game at 70-66 with 3:42 to play and the Sun never again trailed.
The Mystics (13-10) committed nine of their 19 turnovers and were limited to seven points in the fourth — Washington’s lowest-scoring quarter this season.
Ariel Atkins led Washington with 18 points, including 12 in the first quarter.
LOS ANGELES — Nneka Ogwumike scored 22 points, Liz Cambage added 16 and the Sparks beat the Liberty.
Chiney Ogwumike had 12 points and 10 rebounds, Katie Lou Samuelson also scored 12 points and Jordin Canada added 11 points and seven assists for the Sparks (9-11), who won consecutive games for the first time since the end of May.
Nneka Ogwumike made a layup midway through the third quarter to give the Sparks the lead for good at 53-52 and Chiney Ogwumike’s jumper with 1:22 left in the period stretched the lead to 65-57. Crystal Dangerfield made a 3-pointer, Han Xu hit a hook shot and Marine Johannes followed with another 3 to trim the Liberty’s deficit to 69-68 with 4:42 to play but Cambage made baskets to open and cap a 10-2 spurt that made it 79-70 with 2 minutes to go.
Johannes led the Liberty (8-12) with 17 points and Natasha Howard scored 13.
ATLANTA — Cheyenne Parker had 21 points and nine rebounds, Rhyne Howard scored 16 points and the Dream never trailed in a win over the Storm.
Aari McDonald and AD Durr added 13 points apiece for Atlanta (10-11) and Tiffany Hayes scored 10 points. Durr made 4 of 5 from the field and 3 of 3 from 3-point range.
Breanna Stewart, the only Storm player to score in double figures, finished with 19 points on 5-of-14 shooting.
The Dream outrebounded Seattle (13-8) 44-30 — including a 9-2 advantage on the offensive glass.
MINNEAPOLIS — Aerial Powers scored a career-high 32 points on 10-of-17 shooting and Minnesota beat Las Vegas.
Moriah Jefferson and Rachel Banham added 13 points apiece and Sylvia Fowles scored eight points with 11 rebounds and two blocks for the Lynx (7-15).
Powers scored the final six points in Minnesota’s 13-0 opening run and the Aces never led. Dearica Hamby and Riquna Williams hit back-to-back 3-pointers to pull Las Vegas to 44-35 with about 3 minutes left in the first half but Fowles answered with a layup 18 seconds later and the Lynx led by double figures the rest of the way.
Kelsey Plum led Las Vegas (15-6) with 12 points. Jackie Young and A’ja Wilson added 10 points apiece.
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