Based on the 10 games that came before it, the ending of this Pac-12 Women's Basketball Tournament has a lot to live up to.

Four days of nail-biting basketball will come down to a matchup between top-seeded Oregon State and No. 3 seed UCLA on Sunday evening (6 PT/7 MT, ESPN) after both teams earned semifinal victories the hardest way at Key Arena on Saturday night.

The old saying “Iron Sharpens Iron” has played out in Seattle in front of record crowds and the Pac-12 champion will be better for it.

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“This is the No. 1 conference and we’ve been battling all year,” said Oregon State coach Scott Rueck, in the minutes after his team’s 57-55 win over Washington, a victory clinched when Washington guard Kelsey Plum’s runner into the lane bounced off the iron and away at the buzzer. “We have won a lot of games by double figures this year. But close games like this, they build character. Our team found out it can get stops when it needs to.

“This is the perfect lead-in to the NCAA Tournament. Every team is going to be battle-tested, no doubt about it.”

The Beavers reach the title game for the second time in three years, but are still waiting for their opportunity to hoist a trophy. Oregon State lost to USC two years ago, and made an early exit last season in the quarterfinals, a loss that has fueled them since.

“We learned a lot from that experience,” said Oregon State guard Sydney Wiese. “This whole season had a different vibe for us. We still aren’t satisfied.”

The Beavers relied on the stellar defense that has been their calling card all season to keep Washington in check after the Huskies traded baskets with OSU and went into the locker room tied.

But Oregon State clamped down in the second half and Washington shot just 18.2 percent in the final two quarters. Defended by Gabby Hanson, Plum finished with 14 points, well off her season average. Still the Huskies had a chance to send the game into overtime at the end when Chantel Osahor hit a 3-pointer with 36.2 seconds to go to pull Washington within 57-55.

But the Beavers did enough to get themselves back to the title game and a chance to, as Pac-12 Player of the Year Jamie Weisner puts it, “check that off the list”.

UCLA punched its ticket into its third championship game with a 73-67 overtime win over 10th-seeded California, ending the Bears impressive and record-breaking run. The last time the Bruins appeared in the title game in 2013, they fell in a close game to Stanford.

“We always say we aren’t born for this, we are built for this,” said Bruins coach Cori Close. “We have trained hard. We played a top 10 schedule in the country. We’ve been through about every style of play you can imagine. And our players have chosen to be people of character who are willing to do the hard things and make uncommon choices. I couldn’t be more proud of the character of our team and the heart they showed.”

UCLA claimed its spot with a gutsy comeback and the high drama of a shot that changed the face of the game.

The Bruins faced down a 14-point first-half deficit, chipped away to pull close and then tied the game at 61-61 on a huge 3-pointer from the corner by Kari Korver with 7.3 seconds to go in regulation. Korver was 0-for-12 from beyond the arc before she buried the game-turning shot.

That shot gave UCLA the momentum heading into overtime, where they were able to put the game away against an exhausted Bears team, playing into overtime for the second time in three days.

Jordin Canada, who led UCLA with 26 points, said she knew her team “would not back down” when they were down by 14. The Bruins players nodded in the huddle when Close drew up the play to get Korver the ball and they mobbed her when she hit the shot.

“I knew we had the momentum then,” Canada said.

Sophomore Monique Billings, who ultimately got the better of her battle with Cal’s Kristine Anigwe, the Pac-12 Freshman of the Year, said she knew Anigwe was getting tired. Billings finished with 22 points and nine rebounds. Anigwe had 26 points and 11 rebounds and played much of the fourth quarter with four fouls.

“I respect her game so much, but I knew she was getting tired and I just tried to get my body into her and lean into her.”

The Bruins’ win ended Cal’s upstart attempt to earn a spot in the NCAA Tournament by winning a title as the No. 10 seed.

Cal coach Lindsay Gottlieb and her players were emotional after the loss.

“I told them in there, celebrating is the most fun part, and winning is really fun,” Gottlieb said. “But the second best thing in some weird way is having your guts ripped out and feeling like, you know, you want to cry, because that means you left everything out there.

“We still have a lot of room to grow, but I'm not concerned about their character, and I'm not concerned about our talent. I'm excited to move forward and get this off-season going. I'm sure they want a little rest, but I'm really proud of our team. And we will be back.”