Luke Kuechly
The Panthers linebacker Luke Kuechly was named the NFL Defensive Player of the year in 2013. After his final professional bowl campaign at 28, after playing eight seasons in Carolina. Unfortunately, he suffered many concussions throughout his career and subsequently announced his decision to retire.
Andrew Luck
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Rob Gronkowski
After he won his third Super Bowl with New England, the 29-year-old Patriot player took a hiatus from the game. Today it is unclear if he will return but it seems like he has chosen a life of retirement instead. Fans would love to see the tight end return, but it looks like he has no such plans to.
Rob Gronkowski
