For much of three quarters Sunday in their season-opener with Connecticut, the Lynx were, frankly, a little languid.

Coach Cheryl Reeve was both surprised and unhappy about it. The team had showed great energy in camp and in scrimmages.

And then this?

Midway through the third quarter with the Lynx down nine points, Reeve put rookie guard Crystal Dangerfield in the game for veteran Shenise Johnson.

It was a jolt of electricity.

“Great energy,” Reeve said Monday, after going through the film of the game with the players. “Everywhere she was going, everything she was doing, there was a pace to it. And her energy was contagious.”

For the second time in two years, a University of Connecticut rookie helped push the Lynx to a season-opening victory. Last year it was Napheesa Collier and her 27 points. Sunday it was Dangerfield, who played the final 16-plus minutes of the game, scored all 10 of her points in that time and was a plus-17 as the Lynx, energized, stormed past the Sun for a 77-69 victory.

After the game former Lynx assistant Jim Petersen contacted Reeve. Those UConn rookies, he said, just plug and play.

Well, for one night. Let’s not make too much of the parallel. Collier was the sixth overall pick, a rookie thrust into the starting lineup in 2019 because of injuries who went on to win Rookie of the Year honors.

Dangerfield was drafted in the second round. And while Reeve expected her to get minutes from the beginning, it wasn’t like she expected her to play most of the second half and all of the fourth quarter in her WNBA debut.

But she had the hot hand. And, on a team with a new backcourt, Reeve is committed to sticking with the player who has the hot hand. Sunday it was Dangerfield. That might not always be the case.

“Had we seen [Johnson], Rachel [Banham], or Lexie [Brown] kind of hold their own in their minutes, we wouldn’t have been searching for an opportunity for Crystal,’’ Reeve said. ‘‘It would not have presented itself.”

But it did. And after a short stint in the first half, Dangerfield was ready.

“She challenged the guards to be aggressive,” Dangerfield said of Reeve’s halftime message to the team. “Connecticut was dictating a lot of things. We were back on our heels. I made the decision that, when I went in the game next time, to just be aggressive. Do what she’s asking me to do.”

Down 11 with 2:18 left in the third, the Lynx closed the quarter on an 8-4 run to pull within seven.

Then, at the start of the fourth quarter, the Lynx really took over. Down six, Collier missed a shot and the Storm rebounded it. But Dangerfield stepped in front of a Kaila Charles pass, made the steal and scored. On the next possession Dangerfield drove left down the lane and scored and it was a two-point game. Sun coach Curt Miller called a timeout, but Connecticut never got the momentum back.

“She listened,’’ Reeve said. “She had a feel for what we wanted our guards to do.”

As a result Dangerfield proved she deserves to be a part of the guard rotation. The crowded forward position has allowed Dangerfield more opportunity early than for first-round draft pick Mikiah Herbert Harrigan, who didn’t play Sunday. Herbert Harrigan still is learning, Reeve said, and she’s behind starter Damiris Dantas and, essentially Collier, at the power forward position, when she moves to the four in smaller lineups.

Dangerfield is on a team still missing Odyssey Sims and Johnson still is working into top shape. So there will be opportunities.

“Next game she might not get many minutes,” Reeve said. “But she will play. And it’s all about making the most of an opportunity.”