Gary Sheffield To Justin Turner -- Take a Shower, Bro ... To Avoid Killer Zits

Baseball great Gary Sheffield says there's one way sidelined Dodgers player could've avoided his mega-zit emergency this week --- TAKE A DAMN SHOWER!!!!

As we previously reported, Turner was HOSPITALIZED after an ingrown hair got out of control -- got infected -- and forced him to be hospitalized (don't worry, he's ok now).

So, when we saw Gary out in NYC we had to ask how he could've avoided the whole zit mess -- teenagers, pay attention.

There's more ... Gary also tells us the most GRUESOME injury he ever witnessed on the diamond -- a crazy moment in 1995 that came THIIIIS close to ending the player's career.