PHOENIX -- Diana Taurasi has always had a knack for playing her best in the biggest games.

Taurasi scored 31 points, including hitting a 50-footer at the end of the third quarter, to lift the Phoenix Mercury to a 96-78 win over the Minnesota Lynx on Tuesday night in the decisive game of the Western Conference finals.

Taurasi improved to 7-0 in her career in winner-take-all games.

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"There is no player in the world I would rather have on my team," Mercury coach Sandy Brondello said.

Down eight points at the half, Minnesota clawed back to tie the score at 67 before Taurasi took over. She hit a jumper and then connected on her shot from the other side of halfcourt to give the Mercury a five-point lead heading into the fourth quarter.

She then scored the first eight points of the fourth to put the game away and give Phoenix an 80-67 lead with 7:19 left. Minnesota had eliminated Phoenix in the 2011 and 2013 en route to winning the title.

"For the most part, going in to the last couple of minutes of the third, they got the momentum, they were playing well, they were feeling good, they were making us feel uncomfortable," Taurasi said. "Couple of plays turns that."

Taurasi said she hadn't made many halfcourt shots in practice.

"I never make them, I don't think I have made one all year," Taurasi said. "I'll miss them all year to make that one."

Brondello noted the shot got the crowd back in the game after Minnesota had erased a double-digit lead in the final 90 seconds of the third.

"When anyone makes a big shot like that, you just think, OK, it's our night," Brondello said. "The look in their eyes, we just knew."

The Mercury, which had the best record in the league, will face the winner of Wednesday's Chicago-Indiana game.

"I thought that Phoenix played great, they were hard to play against," said Minnesota coach Cheryl Reeve, who was ejected after receiving two technical fouls with 1:58 left. "It's not like we played that bad. I got a good team. I thought that we just didn't get done some things we were trying to do on [Brittney] Griner and then Dee. I saw Dee before the game and I told our staff, 'Dee's got a bounce in her step."

Minnesota, which had made the WNBA Finals the past three seasons, missed its first 10 shots of the fourth, falling behind 85-67 midway through the quarter.

Seimone Augustus had 13 of her 21 points in the third quarter as the Lynx erased a 10-point deficit. Lindsay Whalen had 20 points, eight rebounds and six assists but missed four straight shots to start the fourth quarter.

"Taurasi hits a halfcourt shot, tough shot, that was momentum, that was a momentum play for them," Whalen said. "After that we had a hard time getting stops, we started taking tough shots, they weren't falling, the shots that were falling in the first, weren't."

Maya Moore had 16 points on 6-of-14 shooting.

"We put a lot of pressure on Lindsay, Seimone and Maya to have to make plays," Reeve said. "I got nothing out of my post players. That was unfortunate from an offensive standpoint."

Whalen, Augustus and Moore scored 57 of the Lynx's 78 points. Center Janel McCarville was held scoreless and Rebekkah Brunson had four points and eight rebounds.

Phoenix outscored Minnesota 56-34 in the lane.

"We just had an aggressive mentality tonight," Brondello said. "I thought in the second game we did not and tonight we went back to doing what we do best."

Griner had 22 points, six rebounds and four assists for Phoenix. DeWanna Bonner and Candice Dupree each added 14 for the Mercury.

Phoenix, 29-5 during the regular season, has not been in the finals since winning the title in 2009. The Mercury have won 18 straight home games, last losing to San Antonio on May 23.