Nathan Bannister started the ninth, which was his third inning of work. After a flyout to second base, Bannister gave up two singles through the 5.5 hole, bringing up the top of the ASU lineup.
That top of the lineup has two left-handed hitters, so Andy Lopez went with the lefty-lefty matchup and brought in true freshman Cameron Ming.
"As a pitcher, you always want to stay out there, but coach has what he has in mind, and he stays with his gut," Bannister said after the game. "I'm a hundred percent behind him, and just gotta get after it tomorrow."
Ming came in, and after walking Johnny Sewald to load the bases, went to a 3-0 count on Jake Peevyhouse.
Two strikes later, it was a full count with the game on the line. Peevyhouse lined one to right past the five infield defense to end the game for ASU's fifth walkoff victory of the year.
Bannister had given up just two hits before the ninth.
"I had really good defense behind me," the junior pitcher said. "I just tried to get ahead and my breaking ball was working tonight. I need to keep that up and use my fastball location to get the hitters out. But my up the middle defense helped me more."
UA got runners to second with one out in both the 6th, 8th and 9th innings, but could not convert on any of those opportunities. Arizona was just 3-for-15 with runners in scoring position on Saturday.
"There's small things that are starting to get a little worrisome," coach Lopez explained. "A leadoff double and we don't advance the guy to third base. We strike out in that at bat. So little things that don't equate to Friday night wins. You gotta get the ball on the ground after a leadoff double."
"Everybody's going to focus on that last inning, but this game was decided three, four, five innings prior to the last inning."
The big showdown was between ASU closer Ryan Burr and nation-leading hitter Scott Kingery with two down in the 9th. Burr won, getting Kingery to hit a soft liner to second on the first pitch of the at bat.
Arizona got the scoring started in the fourth inning. An ASU fan interfered with a probable foul ball out while Riley Moore was up to bat. Moore ended up hitting a single to right.
Bobby Dalbec followed that up with a walk, and after a JJ Matijevic pop up to third, Michael Hoard came up.
Hoard, who leads the team in on-base percentage this season, roped a line drive to right-center, bringing in Moore and Dalbec.
Two batters later, Cody Ramer continued to impress, singling up the middle to bring in the third run.
But ASU would take a 4-3 lead in the fourth inning on a Jake Peevyhouse two-run homer that just went over Zach Gibbons' glove against the right field wall.
"You can't leave a ball on a guy that's a dead-red hitter who wants the ball in," Lopez said of that at bat. "You can't expect him not to do something or some type of damage."
The Wildcats tied it up in the seventh. Ramer hit his second single of the night, and after a sac bunt, Scott Kingery drove him in with a double over Peevyhouse's head in left. That was Kingery's only hit of the night. Kevin Newman also went 0-for-4. Not a great showing for the two Golden Spikes candidates.
The two teams will meet again on Sunday afternoon. Xavier Borde will take the mound for Arizona against ASU's Ryan Kellogg. The game will be broadcast at 5 PM PT on Pac-12 Networks.