All of a sudden, Oregon State men’s basketball has a problem slowing down opposing offenses in the first half.

Stanford scored 43 points before halftime Thursday in its 80-71 win against the visiting Beavers. That’s the most OSU has allowed in a first half this season.

That followed the 41 points given up to Oregon in last Saturday’s Civil War game in Eugene. The Ducks won that one, 66-57. OSU has seen opponents score 40 or more points in a first half this season and it’s happened twice in a week.

Beavers coach Wayne Tinkle was at a loss after Thursday’s game.

“It’s frustrating to know why we have these fogs all of a sudden in these last two ball games,” he said in a postgame radio interview, adding that his team’s first-half play against the Cardinal was “horrendous.”

In their respective first halves, Oregon shot 65.2 and Stanford 62.1.

The 80 points the Cardinal scored Thursday is the most in conference against Oregon State, which has slipped out of the top spots in scoring defense and field goal percentage defense in Pac-12 games. The Beavers are now second in scoring defense (67.7) and tied for third in field goal defense (42.9).

For the season, the Beavers are still first in scoring defense (69.1) and fourth in field goal percentage (42.5).

OSU hasn’t given up 80 points since doing so three times in the first four games of the season. In addition, Stanford’s 55.8 field goal percentage is a high against the Beavers this season and just the second time this year that the Beavers have allowed 50 percent.

Back on track

Stevie Thompson bounced back from two subpar games at the 3-point line to make two of four Thursday.

The junior guard has 14 consecutive games with at least one 3-pointer. In 10 of those games he’s made at least two.

Thompson is 11 games from the school record set by Chris Stephens in the 2003-04 season. Gary Payton is second with 22, set in 1988-89.

Hitting at the line

Tres Tinkle wasn’t quite himself Thursday at the free-throw line, where he made six of nine.

The sophomore forward had made 31 of 33 in Pac-12 games and is now 88.1 percent in conference and 85.6 for the season.

The school’s single-season conference record for free throw percentage in is held by Brent Barry, who shot 89.9 in 1994-95. Stephens has OSU’s overall single-season mark at 89.2 in 2005-06.

Led by Tres Tinkle and freshman guard Ethan Thompson, the Beavers seem to have turned the corner at the foul line.

OSU is 65 of 85 (76.5 percent) in the last four games after making 49 of 81 (60.4) in their first five Pac-12 contests. The Beavers are now at 70.9 percent for the season and 68.8 in conference, both ninth in the Pac-12.

Taking and making

Drew Eubanks continued his strong shooting season, making eight of nine field goals against Stanford to improve to 62.3 percent for the season and 54.8 in Pac-12 games.

The junior forward’s season mark would put him seventh in school history. His career shooting percentage of 59.4 is fourth. Eubanks started the season by making at least half his shots in each of the first 11 games and 14 of the first 15.