Kirk Cousins is sacked in the first quarter by Baltimore’s Anthony Levine. (John McDonnell / The Washington Post)

BALTIMORE – For all of the encouraging signs displayed by the Washington Redskins’ offense through 12 training camp practices, Coach Jay Gruden and his charges did not experience a carryover in their preseason-opening 23-3 loss against the Baltimore Ravens on Thursday night.

In a pair of three and outs, the first-team offense mustered just one Kirk Cousins completion for five yards and three Rob Kelley carries for two yards. Then Gruden pulled his starters and sent in his second unit, which didn’t fare much better.

Struggles in the passing game weren’t entirely surprising considering the fact that Cousins was without three of his top four targets — tight end Jordan Reed and wide receivers Jamison Crowder and Josh Doctson — each sitting out with injury. (Cousins did have potential No. 1 receiver Terrelle Pryor but overthrew him in his first pass attempt of the game).

However, Washington’s struggles to defend Baltimore’s pressure up the middle of the Redskins’ offensive line did prove a bit alarming. The Ravens went at the heart of Washington’s line both to thwart the run and disrupt Cousins. And they succeeded.

“We weren’t as sharp as we wanted to be,” center Spencer Long said. “We let a few guys loose. But we can learn from that even if it was just six plays. We can learn a lot from the movement they presented us with. Just in six plays, they gave us a few different blitzes. We just need to get our rhythm. It’s hard to do it in six plays. But it was good to get out, start the process of a game again and knock off the rust. But we need to develop a little bit more. We’ve got a long preseason to get that done. We’ll get better.”

Left tackle Trent Williams said he wasn’t overly concerned because teams don’t game-plan for opponents in the first preseason game.

However, both Williams, Long and Cousins agreed that the Redskins needed to have started better regardless.

“We would prefer to get a rhythm over the time of a whole game. But we always talk about starting fast,” Cousins said. “You can’t wait a whole quarter to get going. . . . We didn’t do enough tonight to start fast.”

Washington’s starting defense had a solid showing during its short work, forcing a three-and-out on the only stand that featured all starters. The second defensive stand featured a mix of starters and backups, and that group of players forced a three-and-out as well.

“We’ve got a lot to learn from that film moving forward, but it was a good start,” inside linebacker Will Compton said. “I feel like [communication] was great across the board. Everyone was ready to set the tempo off the jump, and there was a lot of good energy.”

From there, the starters on both units made way for rookies in need of on-the-job training and backups vying for roster spots.

It was there Washington saw some of the few bright spots Thursday.

Rookie watch: Jonathan Allen

Allen displayed relentless effort to record his first sack as a pro. Allen seemed to be knocking on the door as he repeatedly fired off the ball and repeatedly came close to the quarterback, only to arrive a split second late. But in the closing minutes of the second quarter, Allen got home, as the defensive coaches put it.

He rushed upfield, working to beat his blocker. As Ravens quarterback Ryan Mallett looked to break the pocket and take off up the middle, Allen did a good job of keeping his eyes up while fighting through the block. When he saw Mallett make his break, Allen changed directions, darting back downfield and making a diving tackle before the quarterback crossed the line of scrimmage.

“I was just reacting. You never want to get past a quarterback’s depth, but I saw him step up, reacted and chased him down,” Allen said.

Allen’s fellow Alabama product Ryan Anderson also had a good game, generating pressures and showing good pursuit against the run.

“It was something to build off of. I know what to work on, and I got a good feel for the speed of the game,” said Anderson, who finished with three tackles while alternating between right and left outside linebacker. “I was just trying to play with intensity. I need to watch the film and then build off of this.”

A painful series for the defense

The Ravens’ first-quarter scoring drive wasn’t pretty from a Redskins point of view. First, a pass interference on seventh-round pick Josh Holsey turned a third-and-eight incompletion into a 23-yard gain and first down. Three plays later, outside linebacker Trent Murphy had to be helped off the field with a left knee sprain.

Washington got the stop on that third-and-three play, however, bringing on fourth down, and the Ravens missed a 43-yard field goal. But free agent addition Stacy McGee lined up over the center and gave the Ravens a first down instead. Three plays later, the Ravens reached the end zone.

Murphy left the locker room on crutches and with his left knee heavily wrapped. He’ll have an MRI exam on Friday, Gruden said. Meanwhile, safety Su’a Cravens also will have an MRI on one of his knees, Gruden said. It wasn’t clear when during the first series Cravens suffered the injury, but the injury is believed to be either a hyperextension or meniscus related injury, a source said.

Position battle: Linebacker

Free agent pickup Zach Brown came off the bench for Mason Foster at the second inside linebacker spot on the second defensive stand. Those two continue to compete for a starting role at that spot. Brown showed good range as he ran across the field to make a play. Not to be outdone, Foster came back for the third series (taking Compton’s place at ‘mike’ linebacker, so it was Foster and Brown next to each other) and Foster flew into the backfield to make a tackle on third down, bringing up a fourth down. Foster said after the game that he felt comfortable at the ‘mike’ while making calls and directing traffic. He played that role in his first four seasons in the league with Tampa Bay, so, “It was just like riding a bike,” he said before later adding, “I liked having the keys. Manusky gave them to me and I went out, made the calls, tried to make plays.”

Samaje Perine’s ups and downs

Samaje Perine received plenty of opportunities, but the rookie running back had mixed results while showing some inexperience. He didn’t cover up and got stripped of the ball on one carry. He did recover, but that was a four-yard loss. On the next play, Perine dropped a wide-open pass. He did do a nice job a couple of plays before that of picking up the blitz, setting his feet and knocking the pass rusher back to buy Colt McCoy some time.

On the positive side, with the first play of the second quarter, Perine showed some hard running, picking up the first down on fourth and one. Perine ran for 11 yards on his first carry of the second half and showed some improvement picking up a pass rusher on that same series.

Believe it or not, the opening kickoff of a preseason game means something

Special teams in the preseason always can be telling. Here are the 11 Redskins that trotted out on the kickoff return unit to start the game:

Front line: Ryan Grant, Zach Vigil, Deshazor Everett, Chris Carter, Quinton Dunbar.
Second line: Robert Davis and Ryan Anderson.
Third line:  Matt Ioannidis and Jeremy Sprinkle.
Return men: Matt Hazel and Zach Pascal.

Hazel and Pascal aren’t the usual first team return men. Normally it’s Chris Thompson and Bashaud Breeland in practices with the first unit. But this is the chance for those undrafted rookie receivers to show what they can do. Pascal returned the short kick to the 25 for 20 yards.

More on the Redskins:

When Redskins’ practices end, Josh Norman keeps going. And going. And going.

Joe Jacoby, an original Hog, becomes a student with the Hogs 2.0

He’s not relaxed like Aaron Rodgers, but Kirk Cousins has found his comfort zone

Redskins’ defense will be the focus in preseason opener against Baltimore

D.C. Sports Bog: Scot McCloughan did a Twitter Q&A, and Redskins fans will love his responses