In baseball, a force is a situation in which a baserunner is compelled (or forced) to vacate their starting base (time-of-pitch base) and try to advance to the next base. When a runner is forced to advance to a base, they are forced out if an opponent with possession of the ball reaches that base before they do. Runners are no longer forced to advance to the next base if any runner behind them on the basepaths is put out. A runner at first base is always forced to attempt to advance to second base when the batter becomes a runner. Runners at second or third base are forced only when all bases preceding their time-of-pitch base are occupied by other baserunners and the batter becomes a runner. Explanation A forced runner's force base is the next base beyond his time-of-pitch base. Any attempt by fielders to put a forced runner out is called a force play. The forced runners can be compared to bumper cars. If with a runner on first, the batter hits a ground ball, the batter may run to first, and since two runners are not allowed to stay on one base at one time, the runner who was on first, to begin with is now bumped by the advancing batter over to second. If there already was a runner on second as well, that runner is now bumped over to third, and so on. If a runner is bumped over to the next base by the advancing batter or by another runner who was bumped by the advancing batter, then that runner is considered to have been forced to advance to the next base. If however, with a runner on third, for example, the batter hits a ground ball, the batter may run to first, but the runner on third, not having been bumped by the batter, is not forced to advance and can stay where they are if they elect to do so. Force plays, or force outs, are one of the two ways to get a runner out on a ground ball. For a fielder to get a forced runner out, he needs only to retrieve the hit ball and (1) step on the base in question before the forced runner gets there, or (2) tag that runner before the runner gets there. For example, with a runner on first, the batter hits