[greymule]

This would be a blocked ball if the contact actually prevented the defense from making an out.

Isn't this a blocked ball in any case, but an out only if it prevented the defense from making an out?

If any of the runners are attempting to advance, you kill the ball and rule the runner closest to home at the time of the interference out.

I see a difference between calling an out on a blocked ball because of "runners attempting to advance" and calling an out because the blocked ball prevented "a throw and possible tag on a runner." I can see an out in the latter case, but an out just because the runners were in motion? Rule 8-5-G-3 stipulates, "If the blocked ball prevented the defense from making an out, the runner being played on is called out." Where does it say something about calling an out because runners were attempting to advance?

Even with runners in motion, the ball hitting the on-deck batter doesn't necessarily prevent the defense from making an out.

If a wild throw hits the on-deck batter, why isn't this treated simply as a blocked ball, with the runners sent back to the last base touched at the time of the infraction?

Abel on 3B, no outs. Baker grounds to F3, who throws home to get Abel. The throw has Abel beaten easily, but it is wild, gets past F2, and hits the on-deck batter. Abel then crosses the plate and Baker goes to 2B. Or the ball bounces off the on-deck batter and goes into the dugout.

The runners were in motion. Is Abel out on this play because she was attempting to advance when the ball hit the on-deck batter (was blocked)? If Abel is not out, is she sent back to 3B?