As they prepared for the 2012 season, the Washington Redskins’ defensive coaches and players had aspirations of greatness. After making the leap from the 31st-ranked defense in the NFL in 2010 to 13th during the 2011 season, the unit expected to take another quantum leap this year, thanks largely to a front seven composed of returning starters.

The defense held quarterback Drew Brees and the New Orleans Saints below their usual standards in the season opener, but did allow 339 passing yards. Last Sunday against the St. Louis Rams, the Redskins allowed Sam Bradford to throw for 310 yards and three touchdowns, as wide receiver Danny Amendola racked up 15 catches for 160 yards and a touchdown in a 31-28 Rams win.

But the result paled in comparison to the team’s other losses, with repercussions that will be felt throughout the season. Within the first 13 plays of the game, the Redskins saw right outside linebacker Brian Orakpo (Washington’s top pass rusher the past three seasons) and left defensive end Adam Carriker (one of the team’s top run stoppers) succumb to season-ending injuries. Orakpo tore his left pectoral muscle, and Carriker tore a quadriceps tendon near the base of his right knee.

Suddenly, the unit that was expected to be the strength of the team — shouldering the load while rookie quarterback Robert Griffin III and the offense worked through growing pains — is reeling.

Through two games, the Redskins’ defense has given up 810 yards (fifth highest in the NFL) and 63 points (sixth most). Dating from last season, Washington’s defense has allowed at least 25 points in four straight games and six of its last seven. Already down one starter with strong safety Brandon Meriweather hobbled by a knee injury, the unit must find ways to overcome the losses of Orakpo and Carriker.

“Everybody’s got a plan until you get punched in the mouth,” nose tackle Barry Cofield said. “You go in that ring against Mike Tyson, you’ve got a plan. But when you feel that power, the plan changes. You’ve got to react. You’ve got to react to injuries, you’ve got to react to the team you’re playing.”

The revamped plan now consists of Washington turning to second-year pro Jarvis Jenkins as Carriker’s replacement, and a three-man committee of Rob Jackson, Chris Wilson and Markus White to fill Orakpo’s shoes.

“It is a challenge,” Redskins defensive coordinator Jim Haslett said Thursday. “It’s a challenge for everybody. But we’ve got great confidence in Jarvis, and [backup nose tackle/end] Chris Baker is healthy now, so he’ll get an opportunity to play and see what he can do. Rak, it’s going to be hard to replace because he’s a great player, [two]-time Pro Bowler. But I feel good between the three of them — Rob Jackson, Chris Wilson and Markus White. . . . Maybe they won’t play at Rak’s level, but maybe the three of them can be efficient in certain areas, and we’ll have to do some different things.”

In the meantime, more pressure could fall on the offensive side of the ball, where the Redskins currently lead the NFL in scoring at 34 points a game through two weeks.

“We definitely are going to have to put up a lot of points to help them out until they get their situation on that side of the ball fixed with the injuries and stuff like that,” tight end Fred Davis said. “But I definitely believe the guys they’re going to put in there, Jarvis and Rob Jackson, are going to make some plays.”

The Redskins’ problems go beyond injuries. Washington’s tackling was sloppy Sunday as the Rams rushed for 151 yards on 27 carries. The secondary, an area of uncertainty during the preseason, has continued to struggle against opposing aerial attacks. The Redskins allowed St. Louis to convert seven of 12 third downs for first downs.

Entering Sunday’s game against the Cincinnati Bengals, the Redskins have the second-worst passing defense in the league. They are allowing 315.5 yards and three touchdowns per game through the air.

The Redskins added a new third cornerback, Cedrick Griffin, starting strong safety, Meriweather, and free safety, Madieu Williams, to go with holdover cornerbacks DeAngelo Hall and Josh Wilson.

Penalties and coverage breakdowns have hampered the Redskins, who already have yielded seven pass plays of 25 yards or longer, including a 56-yard bomb and a 34-yard touchdown to the Rams.

Haslett said the breakdowns are inexcusable.

“More than anything, we have to work on our technique in the back end — the double move,” he said. “You get beat on a double-move when you’ve got double coverage, stuff like that shouldn’t happen.”

Just two games into the season, the Redskins insist it’s way too soon to panic, that they have no reason to question the coaches or the system. Sticking to the basics and playing with a sense of urgency will enable them to dig their way out, they believe.

“We’ve got a lot of character and a lot of men in that room who have put in a lot of time and got a lot of energy invested, as well as the coaching staff,” Williams said. “It’s up to us to execute and translate what we’ve been doing on this practice field into the game situations.”

Cofield played on the New York Giants team that started 0-2 and gave up 80 points before coming back to win the Super Bowl in 2008.

“It’s definitely not about where you start,” he said, “it’s about where you finish.”