OMAHA, Neb. — Not even LSU coach Paul Mainieri could foresee the performance by sophomore pitcher Caleb Gilbert on Saturday afternoon against Oregon State.

Gilbert, after all, was assigned the start just because Eric Walker was shut down for the season due to forearm soreness. Gilbert had only started four games this year, and five the year before. In his 52 career appearances heading into the day, he had never finished a complete six innings of work.

But pressed into service, the righty took the hill Saturday for LSU’s most important game of the season — an elimination game against the No. 1 team in the country to decide who would move onto the College World Series finals.

And Gilbert came out on top.

The sophomore righty handed the Beavers just their sixth loss of the season in 7.1 stellar innings of two-hit, one-run ball. He struck out seven and was the pitcher of record in LSU’s championship game-clinching 6-1 victory.

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He cruised through the balanced Beavers lineup and kept them off the scoreboard until his very last pitch, an eighth inning home run served up to OSU third baseman Michael Gretler to break up the shutout bid.

“I wish I could tell you that I went to bed last night and dreamt that Caleb Gilbert would give us seven shutout innings on one-hit ball,” Mainieri said, ‘’and that [Michael Papierski] was going to launch one out each side of the plate and Beau [Jordan] was going to tomahawk a 97-mile-per-hour fastball into the stands. But I’d be lying if I told you that.”

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Gilbert took control of the game early on, setting the top of Oregon State’s lineup in order with a pair of strikeouts in the first inning. Gilbert didn’t allow a Beavers baserunner until Trevor Larnach walked with two outs in the fourth inning.

Gilbert said attacking the strike zone against a “scrappy” OSU lineup was key to his fast and efficient start. It only took him 58 pitches to get through the first four innings, as the Tigers offense spotted him a 5-0 lead.

“I knew going into this game and watching the Alex [Lange] game [yesterday] I had to get a first pitch out or the first out of the inning,” Gilbert said postgame. “I think all the way up until the last inning of this game, we got the leadoff hitter out in every inning, so that was huge.”

“He got ahead of hitters,” Oregon State coach Pat Casey said. “We just — I think our guys got a little frustrated early and weren’t able to get good swings off. Without getting the leadoff man on, it’s hard to do a lot.”

Gilbert finished with seven strikeouts for the day, six of which caught the Beavers looking. He took advantage of a wide outside strike zone to pinpoint his low 90s fastball in tough spots to hit. He said this allowed him to take advantage of OSU’s patience at the plate.

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Saturday’s outing was Gilbert’s first start since May 24 against Missouri, and his longest outing of his career. But over the past two months, he’s been an effective weapon out of the bullpen. In four appearances in this NCAA tournament, Gilbert is 3-0 with just one earned run allowed in 18.1 innings.

Gilbert said he wasn’t intimidated by the win or go home situation against the top-seeded team in the nation. It didn't show either. In two appearances (one start, one relief appearance) against OSU in Omaha, Gilbert pitched 10 innings with just one earned run allowed.

“It’s a surreal feeling to be able to pitch your team, when the back’s against the wall, into the College World Series,” Gilbert said.

The Tigers now move on to their seventh CWS final in program history, and they have Gilbert to thank for the final punch of the ticket.