Few NFL players get to choose the manner in which they retire. For many, the 32 teams will just tell a player it’s time to go by not signing him. It’s a little cold and cruel, but that’s the reality of a sport like football where the competition is fierce and never-ending. One day you’re a star, and the next day you’re nothing.

But for a select few, the process of leaving the game occurs in the exact opposite way. Some players are stars right up to the moment they call it quits, ending their careers when they had, at least, a few Pro Bowl-caliber years left in them. Sometimes injuries suddenly render players like Gale Sayers or Terrell Davis physically unable to play; other times, players simply lose the will to participate (think Barry Sanders or Calvin Johnson). An even smaller group simply decides to switch occupations, like Tiki Barber.

Whatever the cause, some of the NFL’s best players have abruptly decided to pack it in and call it a career before many thought their time was up. With Megatron becoming the most recent member to join these ranks, here’s a look at 12 NFL Players to Retire in Their Prime.