Riley Moore, who led off the inning with a single, scored from third, making the final score 8-7, and the Arizona Wildcats dugout rushed the field with a conference trophy in hand.
It was Arizona's first conference title since 1992, which was also the last year that Tucson hosted a regional game for the NCAA tournament. The Wildcats found out during Sunday's game, that they will host a regional next weekend.
"I'm happy for the University and the community," Head Coach Andy Lopez said. "First and foremost, I cannot say thank you enough to the fans that came out this year. There's no way we do what we did this year, if we're not at Hi-Corbett.
Moore, just a freshman, scored the winning run and had no doubt that his team was going to win once Field stepped to the plate.
"(Field) is such a competitor," Moore said. "You almost get the feeling that even if he hits it at someone, it's going to be hard enough that it gets by him.
"We have a ton of confidence after today, after two walk-off wins against our rival. It couldn't be anything better."
Field, a sophomore, entered the day hitting .379 on the season and finished with two hits in five at-bats. He scored two runs, but had his only RBI in the 9th when he won the game.
"Off the bat, I was just hoping that it would get over his glove," Field said. "I saw him jump and I thought he was going to catch it, but once it got over I knew it.
"We knew that we had to battle and that they would scrap with us. We came up with two big wins against them so we have a killer momentum going into next week."
Arizona State rallied from a six-run deficit to tie the game at seven in the top of the 8th inning on a one out double by Abe Ruiz. The Wildcats had struck early, but were held scoreless for the middle innings.
Stephen "Mad Dog" Manthei was brought on to pitch in the top of the 8th with the Wildcats leading by two. Manthei walked a batter and gave up a single before Ruiz tied the game. He got a double play to end the inning, stranding Ruiz at third base as the go ahead run.
Manthei got the win after pitching a scoreless 9th inning. It was Manthei's sixth win of the year and the biggest of the season.
Arizona will play at home next weekend in the first round of the NCAA tournament. The Wildcats' opponents for the regional will be announced Monday at 9 AM PST on ESPNU.