Drue Chrisman, take a bow!

[RiverRat13]

The impetus has to be from the opponent. The receiving team just batting it backwards would not only be risky for the other team to recover, but would not fit the definition of a touchback. Forcibly hitting the ball would put the impetus on the receiver. That would be a safety if recovered by the receiving team. It would not be considered a muff.