Rob Gronkowski has suggested in the past he sustained multiple head injuries during his football career, but he never put a number on it.

That changed this week.

In an interview with CBS News' Reena Ninan that aired Thursday, the retired New England Patriots tight end approximated he'd sustained about 20 concussions playing football.

"I will let my son play football, but first off, I will educate him on the game. Educate him on what I went through," Gronkowski said.

"I truly believe that any injury you receive is fixable. I went through it. I had nine surgeries, probably had like 20 concussions in my life, no lie. I remember like five blackout ones."

That's obviously a disturbing admission, especially after Gronkowski said in a recent interview with NBC News he endured mood swings late in his career with the Patriots and used to have "a centimeter of liquid" on the outside of his skull.

The 30-year-old also admitted at the time that concerns about CTE (chronic traumatic encephalopathy) played a role in his retirement.

Gronkowski suffered two confirmed Grade 1 concussions during his NFL career in 2013 and 2018, but football players -- especially tight ends like Gronkowski -- endure countless other "minor" head injuries as a result of violent collisions that often go undocumented.

Gronk has playfully hinted at a return to the Patriots down the road, but unless he can guarantee avoiding further brain injury, he might be better off staying away from the game.


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