It was a rough opening game for the Kansas City Chiefs, who lost Pro Bowl linebacker Derrick Johnson to a torn Achilles tendon.
Johnson went down late in the first half Sunday with nobody around and needed to be carted off the field. Kansas City lost another defensive starter, Mike DeVito, in the second half to the same injury in a loss to Tennessee.
''We've got some guys that need to step up and get ready to play,'' Chiefs linebacker Justin Houston said. ''Guys go down all the time and you need to step up.''
Houston had a scare when Jadeveon Clowney, the top overall pick in this year's draft, injured his knee and didn't return in a win over the Redskins.
Coach Bill O'Brien didn't provide much more information on Clowney's health after the game.
''They think it's a good prognosis, so it looks like it's going to be OK,'' O'Brien said. ''He may miss some time, he may not. Who knows? So we'll know better as the week goes on.''
It wasn't clear how Clowney was injured, but it happened late in the second quarter. He looked to be arguing with the team doctor as the pair walked off the field to the locker room a couple of minutes before halftime.
The Rams already lost one quarterback for the season when Sam Bradford injured his knee in the third preseason game. Shaun Hill left St. Louis' loss against Minnesota with a left quadriceps injury. St. Louis also lost defensive end Chris Long to a left ankle injury.
Carolina was without starting quarterback Cam Newton, who fractured his ribs in a preseason game last month. He was declared inactive before the Panthers played Tampa Bay.
Cleveland tight end Jordan Cameron aggravated a shoulder injury after catching two passes for 47 yards against Pittsburgh. The Browns also lost running back Ben Tate to a knee injury. Washington tight end Jordan Reed strained his hamstring at Houston.
Other injuries included Steelers' rookie running back Dri Archer, who left the win over the Browns with left knee and ankle injuries.
Chiefs right tackle Jeff Allen left with a strained biceps. Titans linebacker Zach Brown injured his shoulder.
Bills linebacker Keith Rivers injured his groin in a win at Chicago.
Jacksonville lost safety Johnathan Cyprien and linebacker J.T. Thomas to head injuries at Philadelphia. Miami lost starting linebackers Danell Ellerbee (hip) and Koa Misi (ankle) in the first half in a victory over Miami.
Tampa Bay lost newly acquired guard Logan Mankins to a knee injury in the second quarter.
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