Redskins outside linebacker Preston Smith, center, rushes Falcons quarterback Matt Ryan. (John McDonnell/The Washington Post)

Thursday night’s preseason opener between the Washington Redskins and Atlanta Falcons was a hodgepodge of half-baked snapshots of action as coaches worked to ensure they didn’t subject starters to unnecessary injury, tinkered with lineups and tried to get roster hopefuls adequate snaps for evaluation.

But a pair of young linebackers who figure prominently into the team’s future emerged from the game with two of the better performances of the night, giving themselves sound foundations to build upon as the preseason continues.

Second-year edge rusher Preston Smith may have had a quiet two weeks of training camp — a curious development considering the change in his body (leaner and bigger after taking up a new offseason training regimen) and improvement in football IQ after hours spent in the film room. On Thursday night, he appeared to flip a switch, causing disruption on his pass rushes and playing with greater discipline and determination against the run.

Meanwhile, rookie Su’a Cravens — taken in the same round as Smith, a year later — also sprang to life Thursday night. That served as another encouraging development for the Southern California product and his coaches after a minor hamstring strain, fluctuating snap counts and toggling back and forth between the second and third units stifled him in training camp.

Redskins rookie linebacker/safety Su’a Cravens upends Atlanta's Justin Hardy on a kick return during the first half. (Curtis Compton/Atlanta Journal Constitution, via AP)

Smith played only two full series — both of them three-and-outs — and a couple of snaps after that. But during that time, he generated pressure on Falcons quarterback Matt Ryan three times and recorded two tackles, one for a loss.

Cravens, used primarily as an inside linebacker, played the bulk of the third quarter on defense after lining up exclusively on special teams in the first half and recording a tackle on punt coverage. During that quarter, he played with aggression and displayed a nose for the ball as he recorded three tackles (two for losses), one quarterback pressure and a pass breakup while also playing well in coverage.

Coaches are counting on Smith starting on the right edge and using his speed, size and athleticism to win matchups with left tackles and terrorize quarterbacks. Cravens’s role has a “TBD” scribbled next to it for the time being. But if Thursday’s game is any indication, both could help ignite a defensive unit that lacked consistent difference-makers among the front seven in 2015.

Smith’s play was encouraging because he made good on a prediction about switching from practice to game speed and because he showed greater instincts than he did a year ago.

Explaining his lack of impact in practices, Smith said the constraints, which prevent defenders from hitting quarterbacks, make it hard for him to fully dial in while also trying to ensure he doesn’t injure teammates. But he became more aggressive Thursday night. Smith got into the backfield with a blend of power, speed and countermoves. He also showed off his athleticism when he started one play on the outside, stunted to the inside and barreled down on the quarterback, forcing an incompletion.

Against the run, Smith displayed growth. Last year, he got blocked out of plays at times and struggled to fight through blocks. On Thursday night, on Atlanta’s second offensive play, the Falcons ran right at Smith on a stretch zone play. Left tackle Jake Matthews tried to usher Smith out of the play. But Smith fought through the block, shedding Matthews and dropping running back Devonta Freeman deep in his own territory.

“I’ve just tried to do a better job of taking better angles on runs,” Smith said. “Last year, I wasn’t doing a good job of that, didn’t fight off blocks well, so it’s just stuff I’ve been working on.”

Despite the positive outing with limited repetitions, Smith expressed a degree of disappointment in his play, however.

“It was some great stuff to put on tape, but I’ve got to do a better job of finishing my rushes when I’m close to the quarterback,” he said. “I’ve got to watch the film, I’ve got to modify my game and figure out how to have better finishes so I have more sacks.”

Cravens, meanwhile, displayed the high-energy, roving playmaking ability that defensive coordinator Joe Barry envisioned when he sold General Manager Scot McCloughan on drafting the USC product.

After appearing tentative at times during practices, Cravens flew around, making tackles, covering slot receivers or running backs out of the backfield, and making tackles in the open field and backfield.

On his first couple snaps, Cravens appeared to feel his way along, but he quickly adjusted and began find his way to the ball.

“It wasn’t the speed, so much, just the strength of everybody,” he said. “Everybody’s so big and athletic. I had to change my game and react fast now that I’m a smaller guy and on the inside. But after the first series, I felt like, ‘Okay, I’m all right.’ ”

Cravens drew praise from Jay Gruden even though the coach joked that film review likely would reveal that the performance was far from perfect.

“He was all over the place tonight,” Gruden said. “I’ve got to look at the film. Some of those places he was at he maybe should not have been. But I love his energy, and that’s what I wanted to see.”

Cravens laughed when told of Gruden’s comment. But he agreed.

“It was a good first game,” he said. “I definitely got the little tweaks out of it being my first game. But I felt like I did pretty good today. Made a couple mistakes, but overall I did all right.”