Arik Armstead dealing with broken hand as 49ers' DL depth thins out

Arik Armstead, right, might miss the rest of the season due to a broken hand. Brad Mills/USA TODAY Sports

SANTA CLARA, Calif. -- San Francisco 49ers defensive end Arik Armstead suffered a broken hand in Sunday's loss to the Washington Redskins, an injury that will require surgery and could land him on injured reserve for the second straight season.

Niners coach Kyle Shanahan said the decision on whether to put Armstead on IR has not been made yet but did say Armstead will be out for "some time." In addition, defensive end Aaron Lynch suffered a calf strain against the Redskins that has Shanahan labeling him as "week-to-week."

Suddenly the 49ers' depth on the defensive line, an area considered a strength entering the season, is now questionable moving forward.

"The more guys you lose, the less you like that depth," Shanahan said. "We'll have to [discuss Armstead and injured reserve] over the next couple days and we're going to have Lynch out, too, for at least a week, most likely more. That takes away two guys who were helping. Hopefully we'll get [LB] Dekoda [Watson] back this week, which would help because I know he missed last week with his groin and hopefully getting him back will help that depth and I'm sure we're going to get someone else here."

Armstead has been starting at defensive end all season, playing on most running downs and occasionally coming off the field in pass-rushing situations. He injured his hand in the second quarter before Lynch replaced him. Lynch then left with his injury in the second half.

If the Niners do place Armstead on injured reserve, it would be his second consecutive abbreviated season because of injury. He missed the final eight games because of a shoulder injury in 2016. So far this season, he has 16 tackles and 1.5 sacks through the first six games.

The 49ers already have two defensive linemen -- Tank Carradine and Ronald Blair -- on injured reserve, though there remains a real possibility that both will be brought back this season.

Still, without Armstead and Lynch, chances are the Niners will have to make an addition on the defensive line this week. In their absence Sunday, rookie Solomon Thomas played a whopping 68 snaps, the most of the defensive linemen.

To Thomas' credit, he took advantage of the extra snaps, posting nine tackles and a sack.

"I hope he keeps coming," Shanahan said. "You know, I think he's had, no one just gets better each week. He goes for it every week. I thought he took a little bit of a step back versus Indy and I thought he took a step forward this week. I thought he played relentlessly and he played very hard, kept working, got that sack opportunity and I think he had a number of tackles.

"I don't know the exact number, if it was nine or 10 or something and that's because of how hard he was working. He was doing some good things and he definitely had an effect on that game versus a very good O-Line."

After Thomas, defensive tackle DeForest Buckner was next with 61 snaps, nose tackle Earl Mitchell played 49, defensive tackle Xavier Cooper played 32, defensive tackle D.J. Jones got 18 and end Elvis Dumervil stepped in for 15.

Dumervil remains the Niners' most effective edge rusher, but they are fighting a battle between keeping him fresh and taking advantage of his ability. Will that change now with the latest rash of injuries?

"It's tough because the plan is to try to keep all of those guys fresh," Shanahan said. "I would love to keep Elvis fresh. He's one of our better third down pass-rushers, the way he gets off the ball and he knows how to get to the quarterback. And the fresher your guys are, not just at D-Line, but every position, the better they play, and that's why I think a number of teams around this league keep a lot of D-linemen and do that.

"It's tough as the year goes when you have injuries. You've just got to deal with it. We will always try to keep guys fresh if we can, but that's definitely getting harder as we go."