Arian Foster went down in a heap without taking a hit.
Foster injured his right Achilles tendon late in the fourth quarter of Houston's 44-26 loss at Miami on Sunday. Texans coach Bill O'Brien said he didn't know the severity of the injury, but added ''it obviously didn't look good.'' If Foster tore his Achilles, his season is over.
Foster was starting to run a pass pattern off pre-snap motion when he fell to the ground and grabbed his leg. He was helped off the field by teammates and training staff.
Foster hasn't played a full season since 2012. The four-time Pro Bowl pick missed eight games after having back surgery in 2013, sat out three games last year and three more this season. He has battled groin, hamstring and calf injuries.
In St. Louis, Johnny Football made his first appearance since Week 2 after Josh McCown hurt his right shoulder late in Cleveland's 24-6 loss to the Rams.
Johnny Manziel entered for his first action since he was questioned Oct. 12 by police in Avon, Ohio, after the 2012 Heisman Trophy winner argued with his girlfriend while driving on a highway. He was not arrested and the couple was allowed to leave together.
In other injury news:
-Cowboys RB Joseph Randle left with a back strain in the first quarter.
-Chargers left guard Orlando Franklin injured his knee.
-Lions QB Matthew Stafford had X-rays on his left hand after the game.
-Jets C Nick Mangold left in the fourth quarter after hurting his neck when he collided with a defensive lineman.
-Colts WR Phillip Dorsett, a 2015 first-round pick, injured his left ankle in the first half.
-Redskins LB Ryan Kerrigan broke a hand, LB Perry Riley Jr. sustained a lower leg muscle strain and CB Bashaud Breeland strained a hamstring strain. In that game, Buccaneers WRs Louis Murphy and Vincent Jackson left with knee injuries.
-Falcons WR Leonard Hankerson left in the third quarter with a hamstring injury and S William Moore went out with a groin injury. Also in that game, Titans CB Jason McCourty came out after a hamstring injury and C Andy Gallik is in concussion protocol.
-Bills LB A.J. Tarpley left the game with a possible concussion.
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