Sharon from Lethbridge, AB, Canada asks:
Batter hits a grounder to the shortstop, who spins and throws to first. First baseman catches it but comes off the bag just before the runner crosses. Is the runner safe or out?
As long as the first baseman was in contact with the base when they caught the ball, then the runner is out. However, if the throw pulled the first baseman off the base and the baseman never had possession of the ball while in contact with the base, then the runner will be safe if they can reach first before the fielder with the ball touches the base.
Answered by: Jonathan Bravo