[tysok]

Originally Posted by Bobbert

witout the erroor Sanders would be in second abut is now in third, so if he scores on anythinying but a single i's clearly an earned run. If he however scores on a single I guess it comes down to if he would've been able to score on that single from second or not. (all this assumes that the next batter gets out, else his run would be earned any way)

Is there a good rule for this or is it up to the scorer to decide if he would've scored from second on a single or not? (in this case it's easy as their is a runner on second, but if second would've been empty)

You're supposed to put the inning together as if there were no error and see what would happen. Since the error only allowed extra bases (not the guy to be on base) it wouldn't count as a supposed third out (which means runs following might still be earned).
There should have been men at first and second without the error, instead they're at second and third (maybe it was first and third). If the next batter (A) hits a single it would be scorers judgement if the run would have scored. If he decides it would have scored on the single then it's earned automatically. If he decides it wouldn't have scored, it could still be an earned run if the NEXT batter (B) hits a single. If batter A hit a double, triple, or home run that run would be earned... and since Nichols wasn't actually on base because of the error his run could be earned if he came around etc.