7. Rey Mysterio
Rey Mysterio only just recently returned from an eight month absence following a serious knee injury in March of 2013. And the very next day after he came back on Monday Night Raw, the internet was already buzzing with rumors that he had possibly injured himself yet again on WWE's flagship program. While this has not been confirmed, the truth is that Rey is not a young man anymore and the years of punishment he' s absorbed in the ring are quite possibly beginning to take their toll on his body. He was hurt back in 2011 but as he was recuperating, he was hit for a violation on WWE's Wellness Policy and did not return for nearly a full year afterward. A myriad of minor issues in the 12 months that followed led up to the knee injury and several surgeries that put him out until he returned in November of 2013. At this point, Rey's WWE career has come under fire from many fans due to his physical issues. While I for one understand how important he is to that company in terms of merchandise sales, I can certainly see the frustrations beginning to build among the WWE faithful. It does seem a shame that a future Hall of Fame Superstar's career could end on a down note due to injury but in the world of professional wrestling, it's always a very real possibility.