MINNEAPOLIS — To even their WNBA semifinal series at 1-1, the Phoenix Mercury had to do something no team had ever done in league history.

The Minnesota Lynx had never lost a playoff game in which they led at halftime by double digits (15-0). And they had never lost any game, playoffs or regular season, where they were up 16 or more at the half (61-0).

That is, until Tuesday’s 89-83 Phoenix victory in overtime at Target Center. The No. 4 seed Mercury trailed 48-32 at the break and the top-seeded Lynx looked on their way to a 2-0 lead in the best-of-five series.

Then, everything turned around. The Mercury fought their way back, setting up Phoenix guard Sami Whitcomb’s score-tying 3-pointer with 4.3 seconds left. Then Minnesota forward Napheesa Collier missed a jump shot at the buzzer, sending the game to overtime.

There, the Mercury completed their rally after being down as much as 20. It tied for the largest road comeback in WNBA playoff history, matching the Chicago’s Sky’s 20-point rally against the Atlanta Dream in 2014.

“Nobody said this stuff was gonna be easy,” Lynx coach Cheryl Reeve said.

Phoenix coach Nate Tibbetts, said, “Just pride, toughness, grit. I couldn’t be more proud of our group for doing that. I mean, I’m fired up. Phoenix is going to be rocking on Friday and Sunday (for Games 3 and 4).”

Having lost the series opener 82-69 on Sunday, the Mercury went to the locker room at the break Tuesday with their season hanging in the balance. Going back to Phoenix down 2-0 wouldn’t have felt impossible, but close to it.

So, Tibbetts brought some heat for his halftime address to his team. How much heat? He said, “You’ll have to ask the players.”

Whitcomb said it was an appropriate amount of heat, and the Mercury responded. They outscored the Lynx 22-14 in the third period, and the entire vibe of the game changed.

“They came out really aggressive, especially in transition,” said Collier, whose 29th birthday Tuesday didn’t have the ending she wanted. “We had a lot of turnovers, so cutting back on that would have been a huge difference.”

The Lynx finished the regular season a league-best 34-10 overall and 20-2 at home, then won their two previous home games in these playoffs. But Reeve said she saw mistakes and bad body language from her team in the second half that she wasn’t expecting.

“Suddenly, we lost our way,” Reeve said. “We didn’t respond. Then when we needed to go get buckets and we had good opportunities, we weren’t strong enough. We weren’t tough enough. And they ripped the game from us.”

The Lynx turned the ball over on a five-second violation with 46.8 seconds left, which led to an Alyssa Thomas basket for Phoenix. The Lynx went up 79-76 after Courtney Williams’ two free throws, and the Mercury took a timeout with 20.7 seconds left.

Tibbetts anticipated Minnesota might foul to prevent a score-tying 3-point attempt. But the Lynx didn’t do that, and Whitcomb put up a 3 that was short.

Then Thomas grabbed the offensive rebound and passed to Kahleah Copper, who swung the ball to Satou Sabally, who found Whitcomb again. This time, Whitcomb swished the score-tying shot.

Tibbetts said Whitcomb “saved my ass” by adjusting to how the Lynx ended up defending the Mercury on that sequence. Whitcomb credited her teammates for passing her the ball again after she had missed the first time.

Whitcomb is known for her high-volume practice shooting, and she said that pays off when you hit a game-saving — and possibly series-saving — basket.

“I was joking, you know, 20,000 [practice shots] for one shot,” Whitcomb said. “I’d love to make all of my shots, but I feel like it shows up in moments like that, those big moments.”

Sabally led the Mercury with 24 points and nine rebounds, while Thomas had 19 points, 13 assists and 8 rebounds. Whitcomb had 13 of the Mercury’s 25 points off the bench.

Collier led Minnesota with 24 points and said the Lynx had themselves to blame for letting their big lead slip away.

“I think we beat ourselves,” Collier said. “Unforced turnovers, not taking care of the ball when they were pressuring us. Just keeping our composure in those situations is huge. Definitely, it’s frustrating, but it’s a series. So we need to go to Phoenix and take care of business.”