Melvin Gordon's breakout second season might have come to a premature end after he was carted off the field in the first quarter of Sunday's loss to Carolina.
The Chargers running back injured his left hip when he tried to recover a Phillip Rivers fumble, but Panthers linebacker Thomas Davis landed on Gordon - causing his leg to bend awkwardly.
Gordon entered the game fourth in the NFL with 992 yards rushing, a season after the 2015 first-round pick rushed for only 641 yards for the entire season. He's expected to undergo an MRI on Monday, and San Diego has only three games remaining.
''Obviously, he's had a heck of a year,'' Rivers said. ''... He was obviously a key part of us offensively and it was tough to see him go down. I'm glad that he's OK, in the sense of it's nothing too, too bad, I don't think, but you hate to lose him.''
San Diego suffered another significant injury when this year's first-round pick Joey Bosa stayed in the locker room at halftime to be evaluated for a neck injury. The defensive end, this year's No. 3 draft pick in the NFL draft, was injured while sacking Panthers quarterback Cam Newton and didn't return to the game.
Also Sunday, Miami quarterback Ryan Tannehill limped off the field late in the third quarter of a win over Arizona and didn't return.
Tannehill, who hasn't missed a game in his five-year career, injured his left knee on a hit by Cardinals defensive tackle Calais Campbell. He was replaced by Matt Moore.
In Detroit, Lions defensive end Ziggy Ansah left the game in the second quarter with a shoulder problem, the latest frustrating moment this season for the 27-year-old pass rusher. Ansah, who had 14 + sacks last season, does not have any after also dealing with an ankle injury earlier this season.
The San Francisco 49ers and New York Jets each lost key players to injuries in the first quarter of their late-afternoon game.
Jets running back Matt Forte left the game with a knee injury and didn't return.
For San Francisco, center Daniel Kilgore hurt his leg and also didn't return. The 49ers already had to shuffle their offensive line with left tackle Joe Staley inactive with an injured hamstring, and Marcus Martin stepped in at center for Kilgore.
San Francisco wide receiver Torrey Smith also left the game with a concussion after his helmet slammed against the turf following an incomplete pass in the third quarter. Smith was motionless at first, but he was able to move and sit up in the cart as he was taken to the locker room.
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