Former Giants tight end Daniel Fells announced his retirement from football on Instagram Tuesday night.

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"I wish I was heading into battle with my brothers as training camp starts up this week but I also believe that everything happens for a reason. Although playing the game is no longer in the cards for me I'm grateful for the 10 year career that I was blessed to experience," he wrote.

Fells had a staph infection in his ankle last season that was discovered to be MRSA, which is dangerous because it's resistant to antibiotics.

At one point, doctors thought they would have to amputate Fells' foot. It didn't come to that, but Fells had a rough time in 2015, going through at least 10 surgeries to treat the infection.

MORE: Fells' MRSA battle a chilling reminder of infection danger

Even though he can no longer play football, Fells knows he is "lucky to be alive."

He had an eight-year career with stints in Atlanta, St. Louis, Denver, New England and New York (Giants).