There’s really no other way this was going to end.

Down a run to the preseason favorites, who had easily won the first two games of the series, Arizona did what it had done so many times this season in its final at-bat. But unlike the previous six, this one was for the last Pac-12 title.

Brendan Summerhill roped a 2-run double into the gap in right center with 1 out in the bottom of the 9^th inning, scoring Tommy Splaine and Maddox Mihalakis to give the Wildcats a 4-3 victory over Oregon State on Saturday night at Hi Corbett Field.

It was the seventh walkoff win this season for Arizona (33-20, 20-10) and sixth in conference play. And Chip Hale had a feeling it was going to happen, telling player development director John DeRouin that Summerhill was going to gap one.

“I was right for once in my life,” Hale said. “Why not be a walkoff?”

As regular season champions, Arizona gets the No. 1 seed for next week’s Pac-12 Tournament at Scottsdale Stadium. The tourney begins Tuesday but the UA’s first game is 7 p.m. PT Wednesday against No. 9 Washington (19-29-1), with No. 6 Cal (34-18) on tap for Thursday at 7 p.m.

The Wildcats, picked in the preseason to finish ninth, advance to Friday’s semifinals with one victory.

OSU (41-13, 19-10) had taken a 3-2 lead in the top of the 9^th when No. 9 hitter Jabin Trosky poked a ball inside the first base bag with two out, scoring Easton Talt from second. That came against Anthony ‘Tonko’ Susac, who came in with a man on first and one out for Cam Walty, who was masterful in going 8.1 innings.

“None of this happens without Cam Walty,” Hale said of the senior right-hander, who allowed six hits and struck out eight with no walks. “He kept us in the game.”

Walty allowed a 1-out double before exiting, then after Susac walked Talt he got Jacob Kreig to ground one sharply in the hole at short. Mason White dove on the outfield grass to glove it and then fired just in time to third to get the lead runner, with Richie Morales’ foot briefly coming off the bag but then back down before the runner reached. OSU challenged that play but lost, as it did in the 6^th on an infield single by Summerhill that came around to score and tie the game at 2.

“I trust my guys, no matter what,” Walty said of his defense, which was charged with six errors in the series including four in Friday’s 16-1 loss. “I always tell them if they (mess) something up up, I’m like you’re making that play nine out of 10 times no matter what. So I know that next time you get that ball, I still trust you. You have to flush it and just go back and make the next play. And so knowing what we had to do today, I knew they were going to be ready.”

The UA was outscored 25-3 in the first two games, none of its pitchers looking effective while few batters made good contact. All that changed Saturday, with Walty’s cutter keeping an OSU team that was hitting .307 and averaging 12.4 runs during a 7-game win streak from mounting any major rallies.

“The cutter was probably the best that I’ve thrown all year,” Walty said. “And so when (pitching coach Kevin) Vance I knew that we were like I’m gonna pepper it all game.”

Arizona scored first, manufacturing a run in the bottom of the 2^nd via a leadoff double by Garen Caulfield and then consecutive grounders to the right side by Andrew Cain and Adonys Guzman. OSU went up 2-1 in the 3^rd on a 1-out RBI double from Travis Bazzana and a low liner to center that Casey Hintz—a pitcher forced into outfield duty because of numerous injuries—misplayed.

Walty stranded that runner, though, and five others including a man on third with 1 out in the 4^th.

Arizona tied it in the 6^th when Summerhill and Morales both opened with infield singles. White moved both into scoring position with a groundout and then Caulfield flied out deep enough to bring Summerhill home.

All five of Arizona’s runs in the series to that point had been scored on outs, and before the 9^th the Wildcats were 2 for 20 with runners in scoring position.

“They’re a very good team,” Hale said of Oregon State, who will be the No. 2 seed in the Pac-12 Tournament. “They’re going to be one of the national seeds, for sure. We’re really proud to beat them to win the conference, but we’re going to see them in Phoenix. And obviously we’re staying in the same hotel so we’ll see a lot of them.”

In the 9^th, Splaine led off and was hit by a pitch for the 12^th time this season. It was the second hit batter of the game for OSU closer Bridger Holmes, who after Brandon Rogers struck out trying to sacrifice Splaine walked Mihalakis—who pinch hit for Hintz—and was pulled for Joey Mundt.

Mundt fell behind Summerhill 2-1 before throwing him a slider that he crushed into the deepest part of the field. He said he had prepared himself for such a situation going into the inning.

“I kinda knew where I was coming up in the order,” said Summerhill, a sophomore who was 3 for 5 and leads the team with a .332 average. “I figured my teammates were gonna get on, as we’ve done in the ninth all year. And I kind of just was visualizing, like how that’s gonna feel, what it’s gonna feel like what the crowd is be like. Putting myself there emotionally before it happens.”

Arizona’s 20 conference wins are tied for the third-most in school history. The last two times it got that many, in 2012 and 2021, it reached the College World Series.