Sue Bird's 3-pointer right before the third-quarter buzzer provided a lift at just the right time for the Seattle Storm.
Bird hit a 22-footer to put Seattle up by eight just a minute after the San Antonio Silver Stars had cut a 13-point deficit to one in the quarter.
The Storm then went on a 10-2 run to start the fourth quarter en route to a 78-64 victory over the Silver Stars on Tuesday night.
Bird finished with 17 points and Swin Cash added 16.
"Yeah, that one really hurt us," Silver Stars coach Dan Hughes said about Bird's 3-pointer.
"We didn't get the matchup on that situation, but that's what she does for them. We have to recognize that. She's a good player and is going to make those shots. That gave them some separation to play with after we'd gotten back into it."
Bird rebounded a missed free throw by Jayne Appel, dribbled down the court and pulled up for the 3 with Appel defending her.
"I kind of had a feeling if I accelerated a little bit she (Appel) would back up," Bird said. "I'm not going to be able to shoot over her underneath the basket but I can definitely step back and shoot the 3. Even if I got by her, she could still make a play because she's like 8,000 inches taller."
Bird noticed the crowd's loud reaction to the basket.
"You still have the whole quarter, but I felt a lot of energy after that play from the crowd," Bird said.
Tanisha Wright added 12 points and seven assists for Seattle (11-8), which has won four of five and moved into a tie for third place in the Western Conference with Phoenix.
Scholanda Robinson scored 12 points, Becky Hammon 11 while Sophia Young and Jia Perkins had 10 apiece to lead second-place San Antonio (11-7), which lost its second consecutive game and dropped three games behind conference-leading Minnesota (14-4).
Seattle won its sixth straight home game to improve to 7-1, second best in the league.
The Silver Stars cut an 18-point first-half deficit to one point late in third quarter before the Storm pulled away with a 17-2 run.
Perkins hit a 3-pointer as the Silver Stars cut a 13-point deficit to 53-52 with 1:07 left in the third quarter.
But the Storm responded with a 7-0 run in the final 47 seconds of the quarter. Seattle then outscored the Silver Stars 10-2 to start the final quarter and pushed the lead to 70-54.
"It was about settling down with our defense and getting stops," Wright said.
Appel scored seven points and Young five to ignite San Antonio's third-quarter run. Bird made two 3-pointers to help hold off the Silver Stars.
Seattle shot 14 of 17 (82.4 percent) from the field in the first quarter to lead 31-19. Cash had a team-high eight points as she hit all four of her shots. Seven players scored for the Storm.
"They came out and shot the lights out," Hammon said. "I thought we did a good job to fight and pull back within one, but at that point I think we had just expended so much energy to get ourselves back in the game that we didn't finish well."
Reserve Le'coe Willingham scored seven during a 21-7 Storm run to close out the first quarter after San Antonio led 12-10.
The Storm led by 18 in the second quarter before Roneeka Hodges made two 3-pointers to help cut the lead to 44-33 at halftime.
The Silver Stars have lost six straight in Seattle since a win in 2007.
"They are very good at home and nobody is going to dispute that," Hammon said.
San Antonio rookie Danielle Adams, who averages 14.3 points, missed her third straight game with a right ankle injury. She is expected to be out four to six weeks.