Michael Cohen

Milwaukee Journal Sentinel

JACKSONVILLE, Fla. - Green Bay Packers cornerback Sam Shields is being evaluated for a concussion after making a tackle late in the fourth quarter.

Shields collided hard with running back T.J. Yeldon of the Jacksonville Jaguars during the game's final drive. He left the field under his own power but did not return to the game.

The training staff had not made an official diagnosis of Shields by the time the Packers left the stadium.

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If Shields does have a concussion, it will be his fourth dating back to college. Shields suffered his first concussion during his time at Miami and endured two more with the Packers (2011, 2015).

His concussion a season ago was severe, and Shields called it the worst injury he's ever had. When his head slammed against the ground in a win over the Dallas Cowboys last December, Shields said he blacked out on the field. Headaches lingered for weeks.

He finally returned in the playoffs against the Arizona Cardinals.

"When I went out there to try to work out at first, I still felt it in my head," Shields said during OTAs in June. "Just running, doing physical things, your brain's moving. That's your head, your brain. It's real scary.

"Concussions — one minute you feel better, the next minute you don't. You never know. I didn't want to risk something serious happening and then my career would be over with. I don't like them. The headaches are tough."

Because he is being evlauted for a concussion, Shields was not permitted to speak with the media Sunday in Jacksonville.

Wide receiver Randall Cobb left the game briefly as well. A defender collided with Cobb's lower leg after a short reception in the left flat. Cobb said the hit struck a nerve and forced his leg to go numb.

The feeling dissipated a few minutes later, and Cobb returned to the game.

Cornerback LaDarius Gunter missed a few plays due to cramps.