Trojans turn it over and lose

Reporting from Corvallis, Ore. — 

That issue USC used to have, when there would be so many turnovers the game seemed a comedic performance? It came back Thursday night.

The Trojans committed 19 turnovers and lost to Oregon State, 51-45, in front of 6,654 at Gill Coliseum.

“You can’t turn it over 19 times on the road,” USC Coach Kevin O’Neill said.

Credit Oregon State and its 1-3-1 defense. It trapped Trojans in the corners and on the wings, forcing lob passes that were picked off -- which the Beavers converted, turning 19 turnovers into 22 points.

“They were taking away a lot of what we were trying to do,” said point guard Mike Gerrity, who finished with two points, six assists and three turnovers.

“I thought our 1-3-1 was fantastic,” said Oregon State Coach Craig Robinson, who added that his team tweaked its defense during the week, putting bigger players out front to help shut down passing lanes.

“To be honest with you, we should go right through [those traps],” O’Neill said. “We just didn’t do it. We just didn’t do our job.”

Turnovers are nothing new for USC; it’s just that they haven’t been an issue lately. In their first nine games, the Trojans were averaging 17 a game, but in their last 10, they trimmed that to 11.8.

Despite the giveaways, the game still came down to the final minute. USC trailed, 48-45, and worked the ball around until Marcus Johnson missed a close-range shot in traffic.

Oregon State rebounded, and the Trojans were forced to foul.

USC (12-8 overall, 4-4 in Pacific 10 Conference play) fell to 1-5 in true road games this season, with the only win against UCLA at Pauley Pavilion.

Entering the game in a five-way tie for second place in the Pac-10, USC is now bunched up in a tie for fourth place.

Oregon State (9-11, 3-5), which entered the game tied for last place in the standings, got its second straight big home win against USC. Last season, the Beavers upset the Trojans in overtime, 62-58, ending a 23-game Pac-10 losing streak.

With a double-digit lead early, USC looked as if it was repeating its last performance -- a 26-point win over Washington.

But momentum shifted when Dwight Lewis was called for a technical foul following his transition three-pointer in front of Oregon State’s bench that put USC up 21-13 with 6:02 left in the first half.

After making it, Lewis appeared to make some remark in the direction of the bench. Robinson immediately shouted at the nearby official, “Give him a technical!” and he did.

“Any time you’re going to shoot your mouth off, you’re going to pay a price,” O’Neill said.

After Oregon State’s Calvin Haynes made the free throw, USC turned the ball over on its next three possessions, and the Beavers, behind a chanting crowd on its feet, scored on each of its chances, tying the score, 21-21.

“That was a dumb move by me,” Lewis said of his remark, which he wouldn’t repeat. “I should have been able to keep my composure.”

Lewis finished with five points on two-for-12 shooting, including one for eight from three-point range. Haynes had a game-high 25 points, his second straight game with that total.

USC was led by Vucevic, who scored all 12 of his points in the first half and attempted only one shot in the second.

Vucevic sighed outside the locker room as the team prepared to drive back to Eugene.

“This was frustrating,” he said, between gulps of water. “In the second half, we just stopped playing. I don’t know what happened.”

baxter.holmes@latimes.com