D3K / Lookback not enforced until BR leaves field?

[Greatdaytobeawildcat]

Apologies if it's been asked before, but...

USSSA.

R1 on 3B, 1 out.

Uncaught 3rd strike, unaware BR heads towards dugout (instead of running to 1B), catcher fires to pitcher in circle.

Do you have to wait for the BR to exit the field to enforce lookback rule on R1? (if the BR heads for 1B you would wait for her to reach the base, yes? so assuming that until she exits she still has the opportunity to reach 1B).

 

[marriard]

Balls still live, so yes.

 

[The Man In Blue]

R3 is on third.

Marriard gave the short and easy answer, so I had to add something.

LBR is not in effect until the batter runner is called out or has touched first base.