We play under NFHS rules.
We had a runner on first that took her lead after the pitcher released the ball. The catcher made a throw down to first base to pick her off. The first baseman was blocking the bag with her body and did not allow for a path for the runner to return to the bag. Our runner ran into her and was eventually tagged out. As I understand, the first baseman cannot block the base or the base path without possession of the ball. That would be a textbook definition for Obstruction, correct? The runner should have been safe in my opinion. What's the call?