CORVALLIS – It was as thrilling as it is perplexing Saturday night, Oregon State’s 63-53 win over No. 14 Oregon in Gill Coliseum.

The Beavers were as sharp as they’ve been all season defensively for the final 17 minutes, outscoring the Ducks 33-13 to erase a 10-point deficit and win their third consecutive Civil War game.

It’s not the first magnificent performance this season for Oregon State. The Beavers have beaten the Pac-12’s top four teams in the NCAA NET rankings in Arizona (No. 8), Colorado (18), Oregon (19) and Stanford (27).

In other words, the Beavers have proven they can beat any team in the Pac-12.

Yet, OSU is 4-7 in Pac-12 play, because they’re 0-7 against teams ranked below No. 30 in NCAA NET, including three below No. 100.

Figuring out the 2019-20 Beavers might take a PhD.

“Why do you think my hair is gray?” OSU coach Wayne Tinkle said. “Listen, it’s caused us some sleepless nights. But we can’t do anything about what’s behind us.”

What is becoming clear is Oregon State (14-9, 4-7) cannot rely on its shooting. The Beavers win when they play superior defense, as was the case against Oregon. And likewise, in the wins over Arizona, Stanford and Colorado.

Over its last seven games, OSU is shooting 23.9 percent from three-point range. The Beavers were 5 of 18 from behind the arc against the Ducks. In today’s college basketball game, that’s not going to often win.

But it can when Oregon State collectively rolls up its sleeves and plays the type of tenacious defense it displayed against Oregon. During the final 17 minutes, the Ducks scored only six baskets, five that were incredibly contested.

Tinkle said going back to last summer, defense has been the team’s theme. But perhaps it didn’t quite sink in during non-conference play, when Oregon State was among the country’s top 20 in field goal shooting percentage.

“We’ve got to hang our hat on D,” Tinkle said.

Saturday’s defensive display allowed Oregon State to erase a 40-30 deficit, take the lead with 2:48 remaining on a dunk by Zach Reichle, and widen it during the final minute.

Ethan Thompson didn’t give an inch in contesting Oregon’s Payton Pritchard throughout the game. Pritchard led the Ducks with 16 points, but made only 7 of 21 shots.

“The way Ethan defended tonight, unbelievable,” Tinkle said. “All the screens they set for Payton; he just made up his mind to stay in front.”

The rest of the Beavers joined the defensive party at various stages. It finally merged when the Ducks scored nine consecutive points at the outset of the second half to take a 40-30 lead.

What clicked?

“We didn’t panic,” Reichle said.

Good things began to happen once the defense locked onto the Ducks. Reichle hit a three-pointer to get things going. Tres Tinkle posted up a couple times and scored two tough inside baskets. The Beavers surged past the Ducks at 44-42 on a five-foot floater by Thompson with seven minutes left.

OSU trailed only once the rest of the game.

The strategy didn’t change during Oregon State’s run, Tinkle said.

“It was all the guys. They just dug in,” he said. “Told the guys, that was their run. Now let’s draw a line in the sand, get back in it, and close this out.”

If only it were that simple.

Tinkle stepped on a soap box for a bit, as fan frustration is building over the Beavers’ inconsistencies.

“Everybody has the answer, when chemistry should be built, when you should be your best,” Tinkle said. “I’ve been doing this for a while and every year it happens at different times with different teams. I think tonight’s game is going to go a long way with our guys buying in and believing.”

For the fourth time this season, Oregon State is on the verge of getting its season pointed in the right direction. But following the Colorado, Arizona and Stanford wins came a thud of a loss.

What happens now, as the Beavers return to action Thursday against Utah in Gill Coliseum?

It’s one of the great mysteries of this season. Defense has to continue to lead the charge, as Oregon State tries to find its shooting stroke.

“We have to start shooting better. We can’t freak out about it,” Tinkle said. “I love it (tonight), until the last horn, we had guys diving on the floor. That’s Beaver basketball. If we continue to defend like that, and scrap like that, the lid is coming off the hoop at some point and things will be much better.”

--Nick Daschel | ndaschel@oregonian.com | @nickdaschel

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