I am 23 years old and have had 3 surgeries on the same knee in the past 6 years. I am currently in talks with doctors about going in and having micro-fracture done on that same knee. I play golf for a living (a lot less physically intense of a sport), and let me tell you...if it ever gets to the point where micro-fracture is being talked about, you are in a lot of pain constantly. I am doing this to possibly preserve a golf career, so I can only imagine how much of a hindrance his knee was for him to even go down this road. So just from comparing it to my sitution, I would say that his career would have been missing a lot of time and lost a lot of explosiveness shortly. Abnormal joint wear is not a fun pain to have, its basically a 24 hour a day pain that hurts 10x more when you are actually using it.