CORVALLIS - The visiting team at Goss Stadium led 10-0 heading into the bottom of the fourth and the way Oregon State's Luke Heimlich was pitching, that should not have been a surprise.

Except that the Beavers were the away team on their home field for an NCAA Regional baseball game and Heimlich kept getting out of trouble while OSU made LSU starter Zack Hess pay for every mistake during a 14-1 win Saturday night in front of a stadium-record crowd of 4,009.

Top-seeded OSU (46-10-1) will play Sunday at 6 p.m. against either second-seeded LSU (38-26) or fourth-seeded Northwestern State (38-23), who face off in an elimination game at noon. The Beavers have beaten the Demons and Tigers by a combined score of 23-4 during the regional as they seek to advance to a Super Regional with one more victory either Sunday or, if necessary, on Monday.

Adley Rutschman hit a two-run double in the first inning before Hess walked three straight batters with the bases loaded to bring in three Beavers in the third. Oregon State batted through the order once again while scoring five in the fourth inning to take a 10-0 lead.

Heimlich allowed seven Tigers to reach base in the first three innings, but got a pair of double plays to help him keep LSU scoreless until Jake Slaughter homered to open the fourth.

"The first thing Luke will tell you is he didn't throw well and the sign of a great competitor is when you don't think you threw well and you give up one run," OSU coach Pat Casey said. "We defended like crazy and swung the bat. We played with a lot of energy."

Hess retired the first two batters he faced to open the game before hitting Nick Madrigal with a pitch. Trevor Larnach followed with a single and then Rutschman hit a two-run double that put OSU ahead 2-0.

Heimlich walked Zach Watson to open the bottom of the first and hit Antoine Duplantis before Austin Bain hit an infield single to load the bases with no outs. Daniel Cabrera hit a grounder back to Heimlich, who threw home to start a double play. Nick Coomes popped out to end the inning for LSU.

Slaughter singled to open the second and Beau Jordan was hit by a pitch before Heimlich struck out Brandt Broussard. Hal Hughes popped up a bunt to Heimlich, who threw to second base for an inning-ending double play.

"Our defense was huge today and I was grateful that I was able to start a couple of them," Heimlich said. "Our infielders and outfielders, those plays picked me up when I did not have my best stuff. I was out of rhythm a bit and couldn't find my stuff early on but thankful I had that defense behind me."

OSU added three runs in the third when Madrigal, Larnach, and Michael Gretler each singled to load the bases with two outs. Hess walked Tyler Malone, Kyle Nobach, and Zak Taylor to bring in a run each time as the Beavers went up 5-0.

Grenier led off the fourth with a double and Larnach walked before Rutschman doubled in a run. Gretler reached on an error that scored Larnach before Tyler Malone was hit by a pitch to load the bases.

Nobach walked to bring in a run and Taylor followed with a two-run single that put the Beavers ahead 10-0. Gretler walked in the sixth and Taylor doubled before Steven Kwan hit a two-run triple to push the lead to 12-1.

Madrigal led off the seventh with his third homer of the season.

Heimlich allowed six hits and one earned run in seven innings while striking out three.