The Runner - Rule 7.
Basic rules. Rule 7.01-7.03.
Force Plays. A force occurs only when the batter becomes a runner (by hitting the ball) and a runner is on first. A runner on 1B is forced by the batter (obviously, if the batter flies out, there is no force). A runner on 2B is forced by the runner at 1B, only if the runner on 1st is forced. A runner on 3B can only be forced if the runner on 2B is forced. This means that simply because a preceding runner choose to run to the next base does not mean the runner forces the next runner. A force only occurs when the prior runner must run because s/he is forced. As you know, the consequence of a force is that a fielder can retire a runner simply by touching the base. So, if a fielder with control of the ball tags second, the runner is out at that moment.
How a force out is made. The fielder can either touch the base or tag the runner. It's a force either way. This is important as we'll see later because in order to score a run with 2 outs, all runners must reach the base to which they are forced -- even if they are forced out after the runner crosses the plate. Another thing to think about: if the fielder after touching the base on a force out, tries to needlessly tag the runner (it happens) and drops the ball then, the runner still is out -- unless you rule the fielder never had secure possession of the ball, because a tag of a base requires that.
A force is removed on all runners if the batter is out at first or any preceding runner is forced out -- even if it is a tag force out. See Rule 2 ("Force Out"). In that situation, fielders are taught to yell "tag!" indicating that the force is off and the runner must be tagged. So, if with runners at 1st (R1) and 2nd (R2), if the batter is thrown out before reaching first, the force is off.
An important aspect of this rule is that only one runner can be protected by the base at a time -- and if not forced, it's first-come, first-served, meaning only the first runner (the lead runner) is protected. The other runner can be tagged out. That's why it's good for runners to look up before advancing to the next base -- a teammate may already be there. If that happens, and a force is not already on, the clueless runner does not cause a force on the lead runner. So, the lead runner can stay on the base and remain safe or can run to the next one to make room for the teammate, but then the lead runner is liable to be tagged (not forced) out.
Force Plays. A force occurs only when the batter becomes a runner (by hitting the ball) and a runner is on first. A runner on 1B is forced by the batter (obviously, if the batter flies out, there is no force). A runner on 2B is forced by the runner at 1B, only if the runner on 1st is forced. A runner on 3B can only be forced if the runner on 2B is forced. This means that simply because a preceding runner choose to run to the next base does not mean the runner forces the next runner. A force only occurs when the prior runner must run because s/he is forced. As you know, the consequence of a force is that a fielder can retire a runner simply by touching the base. So, if a fielder with control of the ball tags second, the runner is out at that moment.
How a force out is made. The fielder can either touch the base or tag the runner. It's a force either way. This is important as we'll see later because in order to score a run with 2 outs, all runners must reach the base to which they are forced -- even if they are forced out after the runner crosses the plate. Another thing to think about: if the fielder after touching the base on a force out, tries to needlessly tag the runner (it happens) and drops the ball then, the runner still is out -- unless you rule the fielder never had secure possession of the ball, because a tag of a base requires that.
A force is removed on all runners if the batter is out at first or any preceding runner is forced out -- even if it is a tag force out. See Rule 2 ("Force Out"). In that situation, fielders are taught to yell "tag!" indicating that the force is off and the runner must be tagged. So, if with runners at 1st (R1) and 2nd (R2), if the batter is thrown out before reaching first, the force is off.
An important aspect of this rule is that only one runner can be protected by the base at a time -- and if not forced, it's first-come, first-served, meaning only the first runner (the lead runner) is protected. The other runner can be tagged out. That's why it's good for runners to look up before advancing to the next base -- a teammate may already be there. If that happens, and a force is not already on, the clueless runner does not cause a force on the lead runner. So, the lead runner can stay on the base and remain safe or can run to the next one to make room for the teammate, but then the lead runner is liable to be tagged (not forced) out.