ARLINGTON, Texas - So much of what the Oregon Ducks do is based on rhythm.

It fueled the Ducks last season as they led the nation with 47 points per game and reached the BCS National Championship. Oregon’s 12 penalties and four turnovers against LSU kept them from discovering that rhythm, and the Tigers cruised to a 40-27 victory in the Cowboys Classic on Saturday at Cowboys Stadium.

“It’s something we obviously have to clean up,” Oregon coach Chip Kelly said. “When we’re playing very well, we’re not turning the ball over and we’re not getting penalties and we’re not dropping footballs. A couple of times a drive just gets killed, and it was one of those three things.”

Oregon’s offense, which scored a school-record 611 points last season, posed plenty of challenges entering the game.

The Ducks returned their talented duo of quarterback Darron Thomas, who passed for 2,881 yards and 30 touchdowns, and running back LaMichael James, who rushed for 1,731 yards and won the Doak Walker Award.

On Saturday, James was held to 54 yards rushing and one touchdown, while Thomas completed 31 of 54 passes for 240 yards and one touchdown pass.

The Ducks had only nine first downs to LSU’s eight at halftime and 167 total yards. James found little room to run up the middle, and Thomas’ passes seemed rushed and erratic early on.

“I think we were prepared physically,” James said. “I think we held them just fine up front in the beginning. It was just the penalties. I don’t think we were ready mentally, and we had a lot of underclassmen to deal with who had never played a college football game.”

While he praised LSU and said the Tigers had a terrific defense, Thomas remained defiant when it came to the Ducks. No, LSU’s size had nothing to do with the loss, he said. They also weren’t faster than the Ducks.

“Oregon had self-inflicted wounds that we’ve got to work on,” Thomas said. “That’s on everybody. Everybody’s got to clean it up.”

The penalties and turnovers began quickly. The game’s first drive included three Oregon penalties, and LSU took a 9-6 lead when Oregon’s Kenjon Barner fumbled on a punt return. Barner was drilled by Tyrann Mathieu, who forced the fumbled then held onto the ball for a 3-yard score early in the second quarter.

“False starts aren’t due to effort,” Kelly said. “It’s due to not being locked in mentally. Those are self-inflicted wounds and you can’t play against a good football team like we did tonight and turn the football over the way we did. The drops, the turnovers and the penalties are the things that really killed us.”

The Ducks appeared to find their normal rhythm when they got the ball with 12:57 left in the first half and chewed up nearly eight minutes, capped by a 3-yard James run with 5:16 remaining to put Oregon up 13-9.

LSU then scored 24 unanswered points before Oregon was able to score again in the fourth quarter.

Despite the loss, players and coaches were looking forward to next week’s home opener against Nevada. Thomas said “this is going to show the character of the team.”

“I tell the team all the time this is a 12-round fight,” Kelly said. “We didn’t get knocked out in round one, but we lost round one.”