Video: Watch Astros' Zack Greinke Throw 51 MPH Pitch to Tigers' Renato Nunez

There are curveballs, and then there is the pitch Zack Greinke pulled out of his bag of tricks Monday night.

The Houston Astros starter threw a 51 mph floater to Detroit Tigers first baseman Renato Nunez in the fifth inning—a velocity Nunez probably hadn't encountered since he was a kid:

The power of such a pitch is twofold:

1. The batter never sees it coming. Nobody throws that slowly in MLB.
2. The hitter is trained to react in a split second. The eephus destroys any and all calibrations.

Try it too many times, however, and you'll pay.

The only option left for Greinke is to double down on the lack of speed and to lob the ball to the plate underhanded, Rookie of the Year style. How slow can he go?