In basketball, they often talk about players working back by scrimmaging. Then they might go to the Gatorade League or come off the bench or have a minutes restriction because there isn't a minor league system to rehab in. Seems like a flaw of the NBA to not develop a proper minor league system actually, there's enough basketball talent, not a flaw that the MLB has that. I don't really know what happens in the NFL, but they play 16 (17?) games and not 162, they don't really have the same luxury of time. They also play once a week and not daily. They also don't really seem like models to follow when it comes to injury recovery, frankly. Also, your claim that basketball players "get right back to playing" is just dumb. they take every other game off, occasionally entire seasons.
Anyway, this thread rocks. I came to post how it seems like Luis is about 96% recovered, after the home run it might be about 97.5%.