In last weekend’s Big Ten tournament, the Northwestern softball team knew a loss wouldn’t necessarily mean the end of its season. There were still NCAA tournament bids to hand out — and the Wildcats would later receive one.

But now NU isn’t so fortunate.

The Cats dropped their first game of the NCAA regionals Thursday night in Norman, Okla., losing to No. 13 Oregon State 1-0 in 10 innings. The heartbreaking loss leaves NU one game from elimination and in a bad position — especially since No. 4 Oklahoma is also in the Cats’ bracket.

The loss was about as difficult as any all year for NU (28-25). Despite playing almost flawless defense and getting a great pitching performance from freshman ace Lauren Schwendimann, the Cats couldn’t push across a run against the Beavers (38-19-1).

NU struggled to score runs the same way it did in the Big Ten tournament. This time, though, instead of being shut down by an Iowa or Penn State pitcher, it was Oregon State’s Tarrah Beyster doing the honors. She matched Schwendimann inning for inning, throwing 10 shutout innings and holding NU to five hits.

“We’ve seen her several times before,” senior second baseman Mikie Chambers said. “No surprises, she wasn’t overpowering. She just moved the ball in and out really well.”

In the 10th inning, Schwendimann’s luck ran out. She didn’t get an out in the frame, giving up a single and committing an error before allowing the game-winning double to second baseman Brynnen Guthrie.

“It’s just little plays that you wish went the other way but they didn’t,” Schwendimann said. “Runners were getting on in every inning, and everyone was itching for runs.”

Schwendimann did a good job holding the Beavers scoreless for as long as she did. She didn’t have her most dominating stuff, but still only gave up six hits over nine-plus innings — and only four before the 10th.

Helping her was a tremendous defensive performance. Although mistakes in the field have plagued NU all season, its play against Oregon State was as good as it has been. Chambers in particular had a strong game, likely preventing the Beavers from scoring a run much earlier than they did.

“I really like defense better than offense,” she said. “I just took care of my position.”

The Cats had their opportunities but were unable to make a dent in Beyster’s armor. NU had a couple of chances in the game, particularly in the first inning, when it had leadoff hitter Brett Nakabayashi on second with one out and on third with two outs.

But Erin Jancic and Brooke Siebel — NU’s two best hitters — were unable to drive Nakabayashi home with what could have been the winning run.

“We had runners on, chances to score,” Chambers said. “We had five hits; they had six. And their sixth was the winning hit in the tenth.”

Thursday’s game marked the second time this year that the Beavers have beaten the Cats. In early non-conference play, Oregon State beat Schwendimann and the Cats 5-1. As the scores indicate, NU wasn’t the same team it was two months ago.

The Cats face elimination against Harvard (19-20) today at 2:30 p.m.. If NU can defeat the Crimson, then it will survive to see the weekend.