Donald Courtney

Scenario: USA fastpitch softball rules: Dropped third strike, batter runs to first base. Catcher throws to first base, first base catches the ball and steps on first base. While stepping on the bag, First baseman reaches out to tag the runner as well and loses control of the ball and ball drops. Foot clearly touched the bag first but the first baseman lost control of the ball. Question: Does the out qualify immediately when the fielder's foot comes in contact with the bag or in this case, when the fielder reaches out to apply a tag as well, they must then maintain control of the ball?