The Washington Redskins received a double dose of encouraging news Sunday when MRI exams showed that the injuries suffered by linebacker Brian Orakpo and safety Brandon Meriweather during Saturday night’s preseason loss at Chicago were not major, according to people familiar with the test results.

The MRI results took some of the sting out of a disappointing first-half performance by the starters during a 33-31 loss to the Bears. Orakpo left the game with an injury to the area around his left shoulder and Meriweather exited after hurting his left knee.

According to agent Ben Dogra, who represents Orakpo, the MRI exam taken Sunday by Orakpo showed the injury to be “nothing serious at all.” Dogra expressed confidence that Orakpo will be in the Redskins’ lineup when the regular season begins Sept. 9 at New Orleans, adding: “He will be ready for the opener.”

Orakpo grabbed his left arm as he fell to the ground following a first-half tackle attempt on Bears wide receiver Devin Hester, and he had his shoulder wrapped after being helped to the sideline.

Orakpo said after the game that the injury could be related to the torn pectoral muscle he suffered on the same side in the final game last season. He underwent offseason surgery. Orakpo expressed optimism late Saturday that this injury wasn’t severe, saying it might have been related to scar tissue in his shoulder and pectoral area. Orakpo is among the Redskins’ most indispensable players on defense and was their top pass rusher and sack leader last season.

Another person familiar with the results of Orakpo’s MRI confirmed that the test showed no significant damage.

Meriweather’s MRI exam revealed no serious damage to his knee, according to that person. The Redskins, who are scheduled to return to the practice field Monday, did not provide an official update about either injury.

Meriweather was injured on a touchdown run by Bears tailback Michael Bush. The Redskins signed Meriweather as a free agent in the offseason and he has been one of the team’s two starters at safety in training-camp practices and through two preseason games.

The Redskins’ secondary already had its issues even before Meriweather’s injury was factored in. Bears quarterbacks Jay Cutler and Jason Campbell combined for 224 first-half passing yards Saturday.

But the pass defense wasn’t the only problem while the starters still were on the field. Another area of concern when training camp began — the ability of the offensive line to protect rookie quarterback Robert Griffin III — also showed up Saturday. Griffin was sacked three times in the first half as the starters exited with a 20-10 halftime deficit.

“It was part of the learning curve for everybody,” Redskins wide receiver Pierre Garcon said after the game. “We played against a good defense today. They did well. We’ll see what we did on tape and try to learn from it and see what we can get better at. It was a good learning experience for us.”

The Redskins remained without three injured starters on their offensive line. Right guard Chris Chester could return soon from his absence due to a sprained ankle, and the Redskins hope to have left guard Kory Lichtensteiger back from arthroscopic knee surgery in time for the regular season opener. But the playing status of right tackle Jammal Brown remains unclear as he undergoes treatment on his ailing hip and he and the Redskins cross their fingers that he can avoid another hip surgery.

“Football is a game of injuries,” Garcon said. “You have to have guys ready to step up, to step in, to make plays and do their part. It’s part of football. It’s going to happen throughout the year. It’s part of the game. You won’t always have great protection. But the young guys have just got to be ready to go whenever they get their number called. Robert handled it very well with the pressure in his face. Hopefully we can get better protection. But it’s going to come around and we’ll get better at it all around.”

The Redskins’ only first-half touchdown came on a 91-yard punt return by Brandon Banks. The Bears led 27-10 after returning the opening kickoff of the second half for a touchdown. But the Redskins at least could savor an eye-catching second-half showing by their other rookie quarterback, Kirk Cousins, who completed 18 of 23 passes for 264 yards and three touchdowns. He had a passer rating of 154.1, just shy of a perfect rating of 158.3.

“More than anything, the chance to get to play an entire half is what I’m so pleased with,” Cousins said late Saturday. “I’m getting all these reps and as a rookie, that doesn’t happen a lot. I’m trying to make the most out of the reps I’m getting. I’ve been very fortunate to get as many as I have.”

Cousins, a fourth-round pick in April, has gone about his pro football development relatively quietly while the brightest of spotlights has been on Griffin, the draft’s second overall selection who was named the Redskins’ starter by Coach Mike Shanahan in the offseason. But Cousins played the entire second half Saturday while veteran quarterback Rex Grossman remained on the sideline.

Grossman’s experience makes him likely to be the team’s primary backup to Griffin when the regular season arrives. But Cousins showed Saturday why the Redskins and other NFL talent evaluators feel he has promise. He threw touchdown passes to tight end Niles Paul and wide receivers Aldrick Robinson and Dezmon Briscoe. Robinson finished the night with six catches for 104 yards.

“Any time you can play quite a bit, you get more and more comfortable as the game goes on, understanding what they’re doing defensively and what you’re trying to do offensively,” Cousins said. “It was a good performance. . . . Aldrick grabbing his touchdown, that was all Aldrick. . . . Niles Paul made a great catch in the end zone. Dezmon Briscoe made a great catch in traffic. I’m just throwing to the open guy, and those guys are making it happen.”