A 2/G from B6. A1 takes hand off and fumbles at A3 into EZ. B24 decides to bat the ball out of back on EZ. Enforcement?
A's force put the ball in the endzone loose, so the end result of the play is a touchback. If A declines the foul, it's B's ball at the 20. The illegal batting foul was during a running play, so the basic spot is the end of the related run, the A3. If A accepts, which they surely will, it's their ball, 2/g from the 1 ½.
