Members of the Detroit Lions , notably Aidan Hutchinson, were visibly shaken when Jack Campbell was stretchered off the field earlier this week.
Unfortunately, those occurrences are not out of the norm, and former wide receiver Brandon Marshall has been on the field for a couple of those scary moments, including one that ended a career.
Marshall was a member of the Denver Broncos when his then-teammate, Dominic Hixon, was tackled by Kevin Everett on Sept. 9, 2007. Everett suffered a cervical spine injury that left doctors unsure whether he would ever walk again, but he defied the odds.
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During an interview with OutKick, Marshall also recalled a time while playing at UCF when a teammate of his was airlifted to the hospital. Defensive lineman Paul Carrington, who played 15 NFL games, was injured during a practice before the 2005 season started - he wound up playing the entire season and leading the Conference USA with nine sacks.
"Honestly, it comes with it. In those moments, you’re shocked and you’re really feeling for your teammate or the guy on the field. But once the whistle blows, you don’t get wrapped up in your emotions. You have to have a short-term memory. You’re trained to move forward," Marshall said.
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The Lions on Monday announced "preliminary indications are positive" for Campbell's condition. But "out of respect for Jack and his family, we will not share further information at this time."
"It's positive, you know?" coach Dan Campbell told reporters. "So your prayers are working. Please continue to do that."
Minnesota Vikings tight end T. J. Hockenson caught a pass in the middle of the field and was soon sandwiched by two Lions defenders, including Campbell. Campbell arrived at the contact while falling to his knees and appeared to have his head slanted upward, so he made contact with his facemask rather than his shoulders and arms.
Campbell immediately collapsed and lay motionless, his arms dropping to his sides. On a positive note, Campbell did not require help breathing.
"That's difficult, you know, it's difficult," Dan Campbell said. "You don't ever want to see somebody like that on the field, but when you see Jack, Jack never lays on the field ever, no matter what it is.
"And that's when you're like, it puts it in perspective … when you're in the world we're in, you know, you got to snap back, and it's not an easy thing to do."
OutKick's Armando Salguero contributed to this report.