The Eagles might say they’re still waiting for the diagnosis on Brandon Graham’s lower body injury, but the 12-year defensive end knew it was bad the moment he fell to the grass.

With two minutes left in the first half of Sunday’s game against the San Francisco 49ers, Graham suffered a non-contact injury as he attempted to chase down quarterback Jimmy Garoppolo. Moments later, defensive linemate Fletcher Cox clenched his fist and pounded the field while other teammates kneeled as Graham winced in anguish.

The Inquirer has confirmed Graham suffered a torn Achilles in his left leg. Graham indicated he would be out until 2022 in a tweet he posted after the game.

“We’re fearful of what it might be,” coach Nick Sirianni said. “But we don’t know for sure yet, so I don’t want to say. Obviously, we’re concerned. He’s such a good leader on this team. If we are without him, it’ll be a big blow. He’s a great football player and leader. We’re fearful.”

Graham was just one of several losses as the Eagles dropped the home opener, 17-11, at Lincoln Financial Field.

Right guard Brandon Brooks (chest) and linebacker Davion Taylor (calf) were also injured, and both needed to exit the game. Taylor’s injury seemed less serious since he returned to the sideline, but Brooks was ruled out and he is reportedly scheduled to undergo an MRI on Monday.

Cox became emotional while discussing the loss of Graham. He took a second to gather himself before he said: ”It’s always tough. It was a pretty emotional moment for me to see him leave the field. Me and BG have played so much ball together. That was pretty rough for me.

“He’s in a good spot right now. We’ll talk and we’ll figure out what’s going on. We have his back. It’s football. People get hurt. BG has been my lockermate since I got here. We’ll still get to laugh and talk about things. But it won’t be on the field on Sundays, it’ll be in the locker room.

“I’ll make sure he stays in a good place.”

» READ MORE: Eagles-49ers instant analysis: Birds’ stalled drives in first half prove costly in home-opening loss

Sirianni was particularly cautious throughout the summer in regard to player safety and health. He designated regular rest days for veterans in practices and limited their playing time in the three preseason games. His efforts resulted in the team being relatively healthy at the beginning of the season. Safety Rodney McLeod (knee) is the only returnee from last season who has yet to play this year.

When Graham, 33, went down, he was replaced by Ryan Kerrigan, who signed with the Eagles earlier this year in free agency. Kerrigan, also 33, spent his first 10 seasons with Washington. It’ll take a collective effort to replace Graham, a team captain who is widely considered the heart and soul of the Eagles.

Besides Kerrigan, the Eagles have Derek Barnett, Josh Sweat and rookie Tarron Jackson at the edge rusher. Defensive coordinator Jonathan Gannon could also mix in rookie Milton Williams at defensive end.

“The other team probably won’t hear as much before plays,” linebacker Alex Singleton said with a laugh while discussing Graham. “He’s an emotional leader. He’s always got a smile on his face. I remember when I was still on the practice squad, and he was the guy every day telling me I was going to play one day. He’s that guy for this team, and he’ll still be that guy.”

Meanwhile, Brooks was replaced at right guard by rookie Landon Dickerson, who had a so-so performance in his NFL debut. Another option at right guard could have been Nate Herbig -—who boasts experience across the offensive line — but Sirianni opted for Dickerson, whom the Eagles selected in the second round of April’s draft.

Was that that right choice?

“Brooks has been one of the best right guards in the league for a long time,” right tackle Lane Johnson said. “Tremendous loss for us. Having him out there, might’ve been the difference between us winning and losing. ...

“I think [Dickerson] adjusted well in the second half. I’ve got to go and watch the tape. He’s a massive human being. Once he figures it out, he’s so strong and big, he can just focus on himself. The first time I got to practice with Landon was this week. I’ll get more reps with him and maybe Herbig this week.”

Later this week, Sirianni will begin his preparation as he attempts to rebound from his first loss as a head coach. Simultaneously, he’ll need to deal with adjusting rotations across the depth chart and handling the team’s first round of injuries.

Those responsibilities will include replacing the production of a pair of impact players at key positions with 21 years of combined NFL experience.

“That [stinks] for BG,” cornerback Steven Nelson said. “As a leader, the hard work and dedication he’s gave this organization, I just hope he gets better. It was sad to see him leave the field. He’s a big presence on our team.”