[ctblu40]

As far as OBR is considered, I would call time as soon as F2 gloved the pitch and awarded R1 second base. The reason for this stems from the penalty and AR-1 listed in 8.05.

"PENALTY: The ball is dead, and each runner shall advance one base without liability to be put out, unless the batter reaches first on a hit, an error, a base on balls, a hit batter, or otherwise, and all other runners advance at least one base, in which case the play proceeds without reference to the balk.
APPROVED RULING: In cases where a pitcher balks and throws wild, either to a base or to home plate, a runner or runners may advance beyond the base to which he is entitled at his own risk."

Since the batter did not reach first base, and the pitcher did not throw wild, the balk is enforced.

NCAA rules are similar, but not the same. I would not call time and enforce the balk in this situation in an NCAA game because there are 2 criteria that need to be met.
First, 9-3-PENALTY(1) is the same as OBR in that if all runners including the batter advance 1 base, the balk is ignored (which is not the case in the play above).
Second, 9-3-PENALTY(2) indicates that "the umpire shall call balk in the usual manner, but shall not call "time" until all play has ceased (runners have stopped trying to advance and/or a fielder is in posession of the ball in the infield)." In your discription, a fielder has not yet held the ball in the infield (see NCAA RULE 2).

Also, NCAA Rules allow for R1 to attempt to advance to third on this play, and if he's thrown out at third by F8, the runner is out and the balk is still "acknowledged as it pertains to the batter," ie the pitch does not change the count. (NCAA 9-3-PENALTY-A.R. 3)

Hope this helps.