San Francisco 49ers tight end Vernon Davis claims he was tackled by his groin area by St. Louis Rams safety T. J. McDonald.

And had something to say about it.

The play happened in the third quarter.  espn.com reported Davis tweeted that there should be a rule that a player couldn't be tackled "by his penis."  He called it the "most painful thing ever."

For the record, very few players in the NFL wear a protective cup.

You can see the video here.