The Redskins offense shined on Sunday, despite serious injuries to Robert Griffin III and DeSean Jackson. The Washington Post's Gene Wang and Dan Steinberg discuss the impact these injuries will have and how the team will move forward with Kirk Cousins at the helm. (Meghan Sims/The Washington Post)

It was never going to be enough for the Washington Redskins simply to win Sunday’s home opener after scoring just six points in a gaffe-strewn defeat the previous week.

Redskins fans wanted to see fireworks from franchise quarterback Robert Griffin III and a dazzling payoff for the offseason acquisition of wide receiver DeSean Jackson, known for blinding speed and sure hands.

For roughly four minutes, they got that — until Griffin, racing to his right as he scanned the field for the receiver while being chased by a pair of 242- and 243-pound linebackers, came down awkwardly on his left ankle. The joint turned underneath him just as Griffin threw the ball. He took one more step on his right leg but refused to plant his left leg, keeping it aloft like an injured thoroughbred.

Griffin couldn’t see Jackson make the 19-yard catch, but he surely heard the cheers as his heroics put the Redskins in touchdown range. Washington’s franchise quarterback was lying face-first on the turf in front of the Redskins’ bench, his left ankle turned “in a different direction,” as he later explained, racked with excruciating pain that brought him to tears.

As Griffin lay prone, backup quarterback Kirk Cousins took the field and fired a 20-yard touchdown pass on his first throw. And FedEx Field erupted in cheers, followed by a full-throated rendition of “Hail to the Redskins.” The scoreboard flashed the lyrics of the team’s fight song as cheerleaders gyrated, swishing gold pompons in time.

Still, Griffin didn’t move.

Hovering over him was James Andrews, the noted orthopedic surgeon who had rebuilt Griffin’s right knee following the catastrophic injury he suffered in a playoff loss to Seattle at FedEx Field on Jan. 5, 2013. The doctor’s consultation lasted nearly five minutes yet never impeded the action on the field.

“It sounds cold, but it’s not,” said Redskins Coach Jay Gruden, who couldn’t contain his giddiness after the 41-10 thrashing of the Jacksonville Jaguars. “It’s a very tough physical football game, and that’s why we dress 46 guys. We have to almost anticipate guys [going] down, and you have to plan for the backups getting an opportunity.”

It is the law of the NFL workplace. One body is carted off; another grabs a helmet and takes his place.

Sunday, it was the 24-year-old Griffin, Washington’s franchise quarterback, who was carted off after only recently recovering from reconstructive surgery on his right knee.

Griffin received a diagnosis of a dislocated left ankle; tests Monday will determine the extent of the injury and how many games he’ll miss.

Benjamin Shaffer, an orthopedic sports medicine specialist and team physician for the Washington Capitals, said in the best-case scenario Griffin would miss eight weeks. At worst, the injury could be season-ending. But he cautioned that the severity and recovery timetable were difficult to predict absent the actual diagnosis.

“Ankle dislocations are uncommon,” Shaffer said. “They’re often accompanied by significant leg injury and or bone injury, like fracture.”

Within minutes of Griffin’s injury, Jackson sprained his shoulder when he was driven, shoulder-first, into the ground. Helped off the field, he never returned and may miss next week’s game, too.

The hard hits kept coming, with Washington’s beefed up defense delivering the bulk of them, tying a Redskins record by sacking Jacksonville’s quarterback 10 times.

And Cousins, who has labored in Griffin’s shadow the last two seasons, never looked more brilliant, completing 22 of 33 passes for 250 yards, including two touchdowns. Running backs Alfred Morris and Silas Redd rushed for another three touchdowns.

It was impossible to count the standing ovations that followed among the crowd of 80,037 as Cousins marched the Redskins up and down FedEx Field. It’s a fair guess that 400,000 fists punched the sky before the five-touchdown day was out, coinciding with the refrain “Fight for old D.C.!” that rang out after each score.

Somewhere amid the jubilation, Griffin’s left ankle was placed in an air cast and the franchise quarterback loaded onto a cart and driven off the field. There were tears on his cheeks as he acknowledged fans with a wave, a look of disbelief and fear on a face known for its magnetic smile.

Some fans chanted his nickname, “RGIII!” “RGIII!” as he was ferried to the locker room for closer examination. A few teammates shouted, “We’ve got you!” and “We’re going to play for you!”

After the game, Griffin declined to describe the process by which doctors got his dislocated ankle back into proper alignment. But he thanked fans and his teammates for their supportive words, adding: “We’re always thinking positive.”

William H. Wise II, 32, of Hampton, frantically turned to his smartphone to get updates on Griffin’s injury, even though it unfolded right in front of him. He momentarily panicked, fearing the quarterback had torn up his knee again, which surely meant that his career was over. Once he learned it was an ankle, Wise said he felt better about joining the throng celebrating Washington’s 21-7 halftime lead.

“I’m just glad we kept Kirk,” Wise said. “I love RGIII, but I’m a Redskins fan, so I don’t care if we have Rex Grossman or Colt McCoy back there. As long as we’re winning.”

The Redskins paid dearly to acquire Griffin, Baylor’s 2011 Heisman Trophy winner, in the 2012 NFL draft, trading three first-round and a second-round pick for the privilege.

He rewarded the team handsomely his rookie season, winning legions of fans with his magnetic personality and electrifying on-field ability. Game after game, he out-ran defenders with near Olympic-caliber speed and conjured touchdowns from situations that looked irretrievably lost.

But in the Jan. 5, 2013 wild-card playoff game against Seattle, Griffin’s already tender right knee was hit one too many times. He underwent reconstructive surgery later that month. And though Griffin returned for the 2013 season, he was never fully healed, and the Redskins finished 3-13, dead last in the NFC East for the third time in the last four seasons.

Sunday’s game opened with redemption in the air. Griffin streaked 12 yards on the first play running with the abandon of his rookie season. He threw with confidence, too, plopping a 57-yarder in the hands of Jackson that officials ruled incomplete. It could have gone either way.

But in the NFL, as Griffin knows well, fortunes change in a split second.

Loyalties do, as well.

As joyous fans who had streamed out of FedEx Field reached the Morgan Boulevard Metro station, a man out front was selling beverages.

“Get your cold water!” the vendor barked. “Cold water! Endorsed by Kirk Cousins.”

Brandon Parker and Kevin Merida contributed to this report.