Aidan Meola began Saturday’s game as a bench player, but he finished it as a hero.

After trailing by as many as five runs during a Big 12 Tournament semifinal game against sixth-seeded Texas Tech, second-seeded OSU found itself tied in the bottom of the ninth inning.

The Cowboys turned to Meola, who was pinch hitting for star player Roc Riggio. And on a 2-1 count, Meola sent a deep bomb into left field.

The ball landed in the upper deck of Globe Life Field in Arlington, Texas, for a walk-off home run. It marked a dramatic ending to the Cowboys' 6-5 win and booked their spot in the Big 12 Tournamen championship game.

OSU defeated Texas Tech twice on Saturday to advance. It’ll face fourth-seeded TCU at 5 p.m. Sunday for the conference title.

OSU contained Texas Tech’s bats in the early going thanks to Janzen Keisel. The sophomore pitcher recorded eight strikeouts in four shutout innings to start the contest.

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But Texas Tech’s offense came alive in the top of the fifth inning once Keisel got replaced by Drew Blake.

The Red Raiders erupted for five runs in the inning to claim a 5-0 lead, and Hudson White capped off the scoring spree with a three-run homer.

But OSU responded with a five-run inning of its own in the eighth, and it leaned on another pinch hitter to spark the frenzied comeback.

Freshman Beau Sylvester batted in replacement of Riggio, and he sent a ball into the upper deck in left field for a two-run home run. It marked Sylvester’s second career homer on just 39 at-bats.

OSU then trimmed the deficit to 5-3 via a passed ball, and Carson Benge knotted the game at 5-5 with a two-run single to right field.

Meola then completed the comeback in the bottom of the ninth inning with a walk-off home run. It marked the sophomore's third career homer.

The Cowboys have reached three of the last four Big 12 Tournament title games.

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How to watch Big 12 championship game

WHO: Oklahoma State vs. TCU

WHEN: 5 p.m. Sunday

WHERE: Globe Life Field in Arlington, Texas

TV: ESPNU

This article originally appeared on Oklahoman: Oklahoma State beats Texas Tech to reach Big 12 baseball title game