Before hosting the All-Star game this weekend, the Mercury will try to avenge that defeat and win a 12th consecutive game Thursday night.
Phoenix (17-3) hasn't lost since visiting Connecticut (10-13) on June 12, when Candice Dupree and Brittney Griner missed jumpers in the final five seconds as the Mercury fell 96-95. Katie Douglas scored all of the Sun's points in a tiebreaking 9-2 run that gave the Sun a seven-point lead with 2:57 to play.
Phoenix has since produced the longest win streak in franchise history at 11. Griner's second dunk of the season highlighted a 90-78 victory over visiting Washington on Tuesday.
After an 18-point lead was cut to eight early in the fourth quarter, the Mercury responded with a 10-2 run that included four of Griner's 16 points.
"We are playing really well as a unit," Dupree said. "Third and fourth quarter we let up a little bit defensively. But overall I thought we played pretty well."
Dupree had 19 points and Diana Taurasi provided 18 as Phoenix moved a team-record 14 games above .500. Those two players along with Griner are slated to represent the Mercury in Saturday's All-Star game in Phoenix.
Douglas and Sun rookie Chiney Ogwumike will also participate, but first they will try to lead their team to its second win streak of the season.
Connecticut's victory over Phoenix was part of a six-game run, but the Sun have since gone 2-7. They did, however, snap a three-game skid with an 86-63 rout in Seattle on Tuesday.
Alex Bentley scored 22 points, and Ogwumike shook off a slow start to post her ninth double-double with 14 points and 10 rebounds.
"We don't try to depend on any one player. We try to make sure everyone is playing the basketball we need to," said Ogwumike, the No. 1 overall pick in this year's draft. "Alex was really hot in the beginning, and we loved that because she was able to give us confidence for our shooters and get our posts going and everything."
Douglas struggled again with her shooting, finishing with five points while making 2 of 8 attempts. She had eight points on 2-of-9 shooting in a 90-64 loss to Los Angeles on Sunday.
Douglas had 16 points and went 4 of 5 from 3-point range in the win over Phoenix. The Sun were 10 of 13 from beyond the arc, and Bentley had a team-best 22 points on 9-of-12 shooting. The Mercury's All-Star trio combined for 58 points with Dupree scoring 21.
Dupree and DeWanna Bonner had 22 points apiece in a 76-68 win over Connecticut on Aug. 31 that snapped Phoenix's three-game home losing streak in the series.