Backup quarterback Nate Sudfeld looks to the sideline during the Redskins’ 23-3 preseason loss to the Ravens. (Toni L. Sandys/The Washington Post)

For the past 12 days at training camp, Washington Redskins quarterback Kirk Cousins has worked to develop a rapport with his cadre of new receivers, while the team’s radically overhauled defense has experimented with lineup changes and substitution patterns at nearly every position.

The two weeks’ work in Richmond has included spirited competition for starting jobs at several spots, but the tone has been lighthearted most days, with players stretching to music of their own choosing at the outset and signing autographs for fans afterward. In between is sandwiched two hours of on-field work, with the offense working against a defense that knows its signals, and the defense working against an offense that’s well versed in most of its coverages. What Redskins training camp hasn’t included is a scrimmage against a rival NFL team that would provide a truer gauge of the team’s progress — or lack of it.

That awakening came Thursday at M&T Bank Stadium, where the host Baltimore Ravens proved themselves far more ready to play a regular season game than the Redskins, who stumbled to a 23-3 defeat that smacked of a lack of preparation in all quarters.

“It’s a wake-up call,” said Cousins, whose time on the field was too brief to develop any rhythm, the first-team offense pulled after back-to-back three-and-out possessions. “It showed us, as much as we may have been making some plays in training camp in Richmond and feeling good about what we were doing, it’s a realization that we’ve got a long way to go.”

The loss has no bearing on the Redskins’ upcoming season, but as a bellwether for the state of things one month before the Sept. 10 season opener against the Philadelphia Eagles, it was troubling.

Redskins Coach Jay Gruden reacts to a Ravens touchdown. (Toni L. Sandys/The Washington Post)

The Ravens had no more at stake Thursday night than the Redskins. But their defense took the field with the physicality and palpable pride that has been Baltimore’s calling card these last years, swarming to the ball and sacking each of Washington’s three quarterbacks once. The Redskins, by contrast, looked as if they were just getting acquainted.

There was plenty that Redskins fans hoped to see in Thursday’s preseason opener after the offseason overhaul of the defensive coaching staff, a revamp of the receiving corps and the draft-day addition of several promising rookies.

It was impossible to gauge the big-play potential of wide receiver Terrelle Pryor. The lone ball Cousins threw Pryor’s way — a deep throw to open the game — sailed just above the 6-foot-4 wide receiver’s outstretched fingertips and fell incomplete.

The proceedings didn’t bode well for the Redskins’ running game, which Coach Jay Gruden had indicated he intends to bolster this season. Rookie Samaje Perine, the fourth-round pick from Oklahoma, let the ball squirt out of his hands on a second-quarter carry. And though Perine scooped it back up, it was hardly the first impression that any rookie back would want to make on a team that benched last season’s starter for fumbling too often.

As for the defense, rookie lineman Jonathan Allen, the team’s first-round draft pick, registered the unit’s first sack. But on a single defensive series, the Redskins lost linebacker Trent Murphy to a sprained knee and committed a costly pass interference penalty courtesy of rookie cornerback Joshua Holsey. Then came a penalty on coverage of a field goal attempt that sailed wide. Gifted with a first down, the hosts proceeded to plow through the Redskins’ defense for the game’s first touchdown.

These were just a few of the moments in a desultory night for the Redskins, who, it appeared, had made all the right offseason moves to address the glaring weaknesses that contributed to last season’s 8-7-1 disappointment.

They replaced the defensive coordinator after his unit ended the year ranked 28th for a second consecutive season. And they handed his successor, the attack-minded Greg Manusky, the top three picks in the draft, equipping him with better talent and more depth.

Replacing the 2,000 receiving yards lost with the departure of free agents DeSean Jackson and Pierre Garcon wasn’t going to be easy. Pryor has looked terrific in camp so far, but Thursday’s game offered little insight into the passing game, with Pryor targeted just once and injuries sidelining favorite targets Jordan Reed and Jamison Crowder, as well as Josh Doctson.

The team returns to training camp Saturday in Richmond for two final practices. Asked if he felt the tone needed to be more intense, given the Redskins’ poor showing Thursday, running back Chris Thompson said not.

“There is no part of us that feels good about losing any game, any time,” Thompson said. “I think also at practice we need to have a little fun, because I feel like that builds camaraderie. This game is meant to be fun. . . . Today, I just don’t think we put our best out there.”