Cash was injured when he lunged and appeared to hit Hamilton in the upper leg or hip as the cornerback was making a tackle on Jaguars receiver Troy Williamson. Hamilton was also shaken up, but limped off the field with assistance from one of the Buccaneers.
The injury came with 8:24 remaining in Tampa Bay's preseason game with Jacksonville at Raymond James Stadium. Players from both teams gathered around Cash and prayed as he was being treated by medical personnel.
After the game, Bucs coach Jon Gruden said Cash had movement in his extremities, but he had injured his neck.
"We don't know the exact severity, but he is moving around," Bucs coach Jon Gruden said after the game, won by the Jaguars 23-17. "The signs are good, but it's a scary thing. We're praying for him obviously, but we do have good news from the standpoint that he is moving around."
ESPN.com NFL reporter Pat Yasinskas and The Associated Press contributed to this report.