The MLB has just suspended Nick Castellanos -- one of the league's best hitters -- TWO GAMES ... and it's all because the Reds star flexed in a pitcher's face on Saturday.
For real.
The ban is wild ... mostly because the events that led up to it were all fairly benign when considering the unwritten rules of baseball.
Here's the deal -- Castellanos had homered on Opening Day against the Cardinals, and pimped the hit with a bat-flip and a stroll to first base.
Clearly, the Cards didn't love that .