Football at any level carries serious injury risk. Anyone watching, playing, writing about, reading about or even aware of the existence of football knows this to be true. They know it's even more true at the professional level, where the players are faster and stronger, the hits are harder and the stakes are higher. 

If Week 5 of the 2017 NFL season proved anything -- other than the fact that the Chiefs are the best team in football -- it's that nobody is safe from the injury bug. Everywhere you turned Sunday, there was another player going down with a serious injury. 

Let's recap some of the most notable players that left their team's game and did not return:

  • Bilal Powell, RB, New York Jets: Powell suffered a calf injury during the Jets' win over the Cleveland Browns and left the game in the second half. He was relieved by Elijah McGuire because Matt Forte, who usually splits carries with Powell, was already out with an injury of his own. 
  • DeVante Parker, WR, Miami Dolphins: Parker went down early in the first quarter of the Dolphins' win over the Tennessee Titans with what the team later described as a sprained ankle. 
  • Taylor Lewan, OT, Tennessee Titans: The Titans' starting left tackle left in the middle of the first quarter with a knee injury. He'll have an MRI this week but the Titans reportedly don't believe the injury is serious. 
  • Adam Jones and Dre Kirkpatrick, CB, Cincinnati Bengals: Jones left Sunday's win over the Bills with a back injury, while Kirkpatrick sustained an injury to his shoulder. Jones tried to return to the game for a few plays but had to leave again. Both players were originally said to be questionable to return, but they never did. 
  • Charles Clay, TE, Buffalo Bills: Clay was tackled on a 24-yard pass play by Bengals safety Shawn Williams and suffered an injury to his knee. He was taken into the medical tent on the sideline and eventually carted back into the locker room. 
  • Haloti Ngata, DT, Detroit Lions: Ngata was dealing with a several injuries over the last several weeks and his balky elbow caused him to leave the Lions' game against the Carolina Panthers midway through the second quarter. He was eventually sent to the locker room for testing. 
  • Terrance West, RB, Baltimore Ravens: West carried two times for 17 yards in the first quarter of the Ravens' win over the Raiders before being taken off the field due to a calf injury. He was ruled doubtful to return to the game and he did not do so. 
  • Odell Beckham, Brandon Marshall, Sterling Shepard and Dwayne Harris, WR, New York Giants: Yeah. This was a bloodbath for Big Blue. Beckham suffered a fractured ankle and will need surgery. He could be done for the year. Marshall and Shepard suffered sprained ankles, and Harris fractured his foot. Harris is out for the season. The Giants ended the game with Roger Lewis Jr. as their only healthy wide receiver. 
  • Lane Johnson, OT, Philadelphia Eagles: Philly's best offensive lineman exited in the third quarter with a head injury and was quickly ruled out. The Eagles have not yet confirmed whether or not he has a concussion, but if he does, it would be difficult to imagine him playing this Thursday. 
  • Kevin King, CB, Green Bay Packers: Expected to lock horns with the Cowboys' Dez Bryant throughout most of the afternoon, King instead left the game early due to a concussion sustained in the first quarter. The injury forced the Packers to turn to Damarious Randall, last seen leaving the field after an argument with the coaching staff last week; he eventually was the beneficiary of a Terrance Williams drop, which turned into a game-changing pick-six. 
  • J.J. Watt and Whitney Mercilus, EDGE, Houston Texans: The Texans lost a game to the Kansas City Chiefs on Sunday night, which isn't great, but they may have lost their season as well. Watt left the field with a leg injury in the first quarter and was carted off the field, and eventually taken to the hospital. He suffered a tibial plateau fracture and is out indefinitely. (Previous players that suffered this injury missed anywhere from six weeks to the rest of the season.) Mercilus sustained a torn pectoral on the first series of the game and is out for the year. 
  • Chris Conley, WR; Travis Kelce, TE, Kansas City Chiefs: Conley blew out his Achilles attempting to recover an onside kick late in the Chiefs' win over the Texans. He is out for the season. Kelce took a big hit in the second quarter and though he came back in for a few plays, he did not return to the field in the second half. The Chiefs announced that he has a concussion. 

And that's not even all the injuries. Those are just the very notable names that even most casual fans would know. Sunday was a busy, busy day for NFL trainers.