Some have came up with some ideas to move him to a different position to save a little bit on his legs, such as 1B or a corner OF position. With him moving to 1B, he's never played the position before, and who knows how he would adapt to it. With him moving to a COF position, the sudden stops and going into the corners could be more damaging than playing Centerfield.
However, I'm not concerned with his health. The way I look at it, there is a very high risk of him getting hurt no matter what position he plays. He has proved that he can still field with the best of them, he just doesn't have very good range anymore, which is understandable, he's in his late 30s, and has had numerous surgeries on his legs.
Basically what I'm saying is, move him to a corner position. If its worse on his legs, will we get 1/4 of a season instead of 1/2? The sudden stops and cuts might be harder on him, but it will improve our OF defense (which is very important IMO).
Just a random thought I had while reading some other thread.