Despite Miami's upset win over the Bills this past weekend, the 'Phins experienced a scary moment when Tua went down hard on a play and had difficulty getting back up.

After the game, Tua stated that he was experiencing back spasms, but we're suspicious of that claim. The NFL is investigating this moment to see if the Dolphins didn't violate concussion protocols by allowing Tua to return to the game so quickly.

What do you think?

Check the clip out below.