Booger McFarland explains how the Rams' second-half play powered their win over the Raiders and why he believes they will be a team to look out for. (1:19)

OAKLAND, Calif. -- It was the first series of the season opener and a long-anticipated look at the Los Angeles Rams' new star-studded defense. The result was hardly what was expected.

Under a pile of blue-and-white jerseys, Oakland Raiders running back Marshawn Lynch ran up the middle, dragging a pile that included defensive linemen Aaron Donald, Ndamukong Suh and Michael Brockers, among others, across the goal line for a 10-yard touchdown.

If anything was apparent Monday in the Rams' 33-13 victory over the Raiders at Oakland-Alameda County Coliseum, it was that the made-over defense needed at least a half to come together and knock off any rust. And there's still plenty of room for improvement.

"That's just the first game jitters man," cornerback Marcus Peters said after the game. "You know how things go."

The Rams appeared out of sync from the start, as the Raiders amassed 254 yards of total offense in the first half, including 113 receiving yards by tight end Jared Cook, and took a 13-10 lead into halftime.

"I think that tempo kind of caught us off guard," Peters said.

Marcus Peters (22) celebrates with Marqui Christian (41) after returning an interception 50 yards for a touchdown on Monday. Kirby Lee/USA TODAY Sports

Rams coach Sean McVay agreed that the Raiders' offense caused some confusion, in part because there was no game tape to study of new coach Jon Gruden's scheme.

"There were some things defensively, we can clean up our communication, but at the same time, I thought they did a great job -- the Oakland offense -- being able to provide a variety of exotic looks out of some different personnel groupings," McVay said. "It forces some communication at a speed that is tough."

But the Rams' defense made adjustments after the first half and posted a shutout in the second.

"Like a free-style game," said cornerback Aqib Talib, who the Rams acquired in an offseason trade with the Denver Broncos. "Nothing really on tape, real bland stuff on tape and they ran a real offense today. So had a half to kind of trade blows with them and then second half had a good feeling for what they was trying to do."

Cory Littleton, a first-year starter at inside linebacker, intercepted a haphazard pass by Derek Carr with less than eight minutes to play and the Rams converted the turnover into a field goal.

Then with less than two minutes to play, Peters, acquired in an offseason trade with the Kansas City Chiefs, intercepted a pass and returned it 50 yards for a touchdown to put the game out of reach.

"We are just getting started, you feel me?" Peters said. "You see how we looked pretty cool."

Monday's game was the first that the Rams' new defense played together competitively.

Aaron Donald, the reigning NFL Defensive Player of the Year, reported 10 days before the opener after signing a six-year, $135-million contract extension, to end a contract dispute that dated to 2017. He participated in six practices before playing Monday.

The remainder of the defense, including Suh, Peters and Talib, played only two series -- seven snaps -- in Week 3 of the preseason.

"There's a lot of things that we'll learn on film, things that we have to correct and go from there," said Suh, who signed a one-year, $14 million free-agent contract, and finished with four tackles and a quarterback hit against the Raiders.

Donald, who held out of training camp for a second consecutive season, said that he was prepared to play, but was unsatisfied with his performance. He finished with a tackle.

"I just got to do things better," Donald said. "Second-guessing myself on certain things, but like I said, just got to keep playing better."