"No pain, no gain", goes the age-old saying. But how much pain can one actually endure while climbing his way to the top? It's true that oftentimes, players will fake injuries in hopes of getting the referee to foul their opponents. However, sports fans will also attest to seeing some real, gruesome, chilling, and cringe-worthy injuries with major and severe repercussions on the player, including massive surgery, forced retirement, or even lifelong paralysis. For those of you who are not of the faint of heart, we've compiled a list of the most painful injuries to ever happen in sports.