Green Bay linebacker Clay Matthews does not understand why he was flagged — yet again — for roughing the passer, this time while sacking Washington's Alex Smith on Sunday. Matthews said he thinks it's an indication that the NFL is "getting soft."

Even Smith wasn't sure about the call that came late in the third quarter of host Washington's 31-17 victory. Neither were other players or coaches from both sides. Matthews broke free, grabbed Smith with both arms and took down the QB in a seemingly straightforward manner.

"When you're tackling a guy from the front, you're going to land on him. I understand the spirit of the rule. When you have a hit like that, that's a football play. I even went up to Alex Smith after the game and asked him: What do you think? What can I do differently?" Matthews said.

"That's a football play. I hit him from the front, got my head across, wrapped up. I've never heard of anybody tackling somebody without any hands. When he gives himself up as soon as you hit him, your body weight is going to go on him."

There are sure to be more questions and more debate around the NFL about what constitutes a penalty on such plays. Matthews has been called for roughing the passer in each of the first three weeks of the season.

"I had judged that the defender landed on the quarterback, when he was tackling him, with most or all of his body weight, and that's not allowed," referee Craig Wrolstad said, according to a pool report. "That was basically my key — that he landed on him with most or all of his body weight."

Injury report

The 49ers are bracing themselves for the worst, thinking quarterback Jimmy Garoppolo will miss the rest of the season after he injured the anterior cruciate ligament in his left knee Sunday.

Garoppolo will have an exam to confirm the severity of the injury, but coach Kyle Shanahan said: "We fear an ACL. We'll find out more tomorrow." That would mean C.J. Beathard is in line to start.

• Packers defensive lineman Muhammad Wilkerson was carted off because of an ankle injury, and right tackle Bryan Bulaga left because of a back injury.

• Rams Pro Bowl cornerback Marcus Peters had to be helped off the field after injuring a leg.

• Jacksonville defensive end Calais Campbell suffered a right ankle injury.

• Cincinnati star receiver A.J. Green suffered a groin injury.