When OBS turns into an Illegal Block in the Back

[teebob21]

12U ASA State Tournament last weekend. R1 on 1B, batter hits a gapper to the fence. F4 sets up for a throw that is never coming on the inside corner of 2B, facing left field. I come inside the diamond between 1B and 2B (thus looking at R1's back) per USA mechanics. R1 simply runs over F4 from behind with forearms extended, at which point I call OBS as well as point and say "You can't do that, R1!". R1 rounds 2B, stops to look at me, then continues to 3B where she is caught in a rundown and tagged out in the confusion.

I call dead ball, and send R1 back to 2B, as I judged she was unlikely to make it to 3B after taking the time to flatten F4 on her way around the bases. At this point, I warn the player, head coach, and the team that no more rough play or unsporting conduct is allowed.

In the moment, I was ready to auto eject. The rundown gave me enough time to re-process what I had seen, and I decided not to toss the 12 year old. Between innings, I asked my partner if he thought I should have ejected....he said no, but in hindsight, I should have gotten his feedback at the time of the play, as I only saw the collision and did not see her extend the forearms.

What say you? Eject on the spot or warn? I think I should have tossed her.