I'm less worried since he has a pro team rehab staff working to get him back, but he wasn't the most mobile before, and it typically takes 2 years to get the "trust" back in your body (from all reports). I don't necessarily think that's true for a sport like baseball unless you're a catcher, pitcher or a guy who really relies on his legs for speed/defense. Sure it might take more time after he comes back to get all the strength back, but this isn't football or basketball where that's more true since you are constantly running, jumping, cutting, starting/stopping, getting hit, etc. When I tore my acl the first time, the last thing in all sports to come back for me was hitting in baseball. I didn't trust my knee to rotate on my back foot when I swung. It was a total mental thing though, and I didn't realize I was doing it.