Redskins safety Montae Nicholson intercepts a pass before running it back 96 yards for a touchdown in the first quarter of Thursday’s loss to Cincinnati. (Toni L. Sandys/The Washington Post)

The Washington Redskins’ defense has moved in slow motion during most of the past three weeks of training camp. There was no lack of effort in practice, but coaches reined the defenders in a bit during team periods to allow the offense to get complete reps. With Pro Bowl tackle Trent Williams missing and Ereck Flowers transitioning to guard, the left side of the Redskins’ offensive line has struggled and a lack of protection was throwing everything off offensively. The players on the opposite side of the line of scrimmage purposely worked at three-quarters speed.

But their leashes came off Thursday night.

Washington’s first-team defense didn’t play in the exhibition opener last week against the Cleveland Browns, but there it was at FedEx Field against the Cincinnati Bengals, missing only injured linebacker Shaun Dion Hamilton and with first-round rookie Montez Sweat playing in place of linebacker Ryan Anderson, who rotated in later. As it held Cincinnati scoreless in the first quarter of an eventual 23-13 loss, the defense looked like a group with some pent up aggression that hadn’t hit anybody in months.

“We kind of just wanted to touch somebody else, tackle somebody else,” safety Landon Collins said. “That’s the kind of feeling we have, to go out there and attack. That’s what we did. It felt awesome. [The coaches said:] ‘Y’all go ahead. Y’all are unleashed.’ That’s what we’ve been waiting on.”

The officials believed the Redskins were being a little too aggressive during their first defensive series, and Allen and cornerback Josh Norman were both flagged for unnecessary roughness. Norman also earned a unsportsmanlike conduct penalty for an animated interaction with an official.

The penalties helped the Bengals move into the red zone, but a defensive unit that is expected to be the strength of the Redskins’ eventual 53-man roster didn’t break in the shadow of its own end zone. Bengals quarterback Andy Dalton dropped back on third and seven from the 11-yard line and threw over the middle, but defensive lineman Daron Payne got his giant mitt on the pass and tipped it skyward. Safety Montae Nicholson zeroed in on the floating ball and picked it off at the 4-yard line. He ran 96 yards with a convoy of Payne and Sweat and strode into the end zone for a 6-0 Redskins lead.

“We just came out there and showed what we’ve been doing all camp,” cornerback Quinton Dunbar said, “which is getting better, creating turnovers each and every day. We didn’t really talk about it, but you could just tell by the reactions. Through the course of camp things were getting edgy. We were just ready to get out there. . . . Creating turnovers, that’s all we talk about. . . . We’ve definitely been working on that throughout camp, and it’s just going to travel over to the real games.”

The first-team defense played most of the first quarter, which meant three series on the field. After the interception, the Bengals went three-and-out on their next two possessions.

“That’s what we’re trying to do,” Collins said. “We’re trying to get off the field with three-and-outs as much as possible, get as many turnovers as we can.”

The Redskins’ offense continues to be a work in progress without an established starter at quarterback and an unsettled left side of the line. There are potential playmakers at wide receiver, but they haven’t exactly been dominant during the preseason. This team will rely on its defense to win games, and Thursday was an example of what the starters can do.

Depth may be an issue. Hamilton sat out with a chest injury, and rookie inside linebacker Cole Holcomb was out with a shoulder injury. The team is already thin at the position after it lost Reuben Foster to a torn ACL in organized team activities and released Mason Foster right before training camp began. The defensive line depth also took a hit Thursday when Tim Settle left with a sore knee after Caleb Brantley (foot) and Jordan Brailford (groin) had been held out of practices.

Regardless, big things are expected from the defense, and it showed why once it was finally allowed to play at full speed.