How the runner and hitter approach this
play depends on a number of variables
and the philosophy of the coach.
Some coaches require their hitters to hit “behind the runner” on a hit and run meaning they want them to hit the ball to the right side so that the base runner has a better chance of being able to go from 1st to 3rd on the play. Other coaches make it a bit easier on the hitter and just tell them to pull a pitch on the inner half and hit an outer half pitch the other way. They do this because hitting the other way on any pitch (especially one on the inner half) is a very difficult skill for most young hitters. Another option for a hit and run is to try to score a run with one swing of the bat. This may be a better option when a good hitter is at the plate, a not so fast runner is on first, and the next few hitters are not that strong. This option has the hitter at the plate be more aggressive and try to drive the ball into the gap so the moving runner has a good chance to score from first base. To some coaches, telling a good hitter to just hit a ground ball to protect a runner is seen as a waste of a good hitter’s at-bat. The hitter is still forced to swing but his responsibility is more tailored to his ability. The risk with this version is that the batter is not forced to hit a ground ball and may hit a line-drive or pop-up at someone which doubles off the runner. A coach must also be a bit more selective with this play because, ideally, he'll want to pick a situation where the hitter is more likely to get a fast ball strike.The “Run and Hit.” This version of the hit and run usually involves a base runner who has some speed and therefore may have the ability to just steal a base without the hitter protecting him. It’s sort of a cross between the last version of the hit and run I discussed and a straight steal. Many times a coach will tell a hitter to take the next pitch if the coach is fairly certain the runner will be safe on the steal to second. This enables the batter to hit with a runner in scoring position. The “run and hit” version has the runner at first try to steal second base as normal. The batter, however, does not have to swing. If it is a strike, the batter should be hacking to try and score the runner all the way from first or at least get him to third. If the pitch is out of the strike zone, the hitter is allowed to take it because it is likely the runner will steal successfully anyway.
Some coaches have different signs for each version and some, as mentioned above, just go with one version for everyone. Other coaches have one sign but tell certain hitters to address it differently if they get the sign. Whatever a coach decides is based on their philosophy and their personnel. Regardless of why or how they do it, moving runners on the pitch can be a big part of an offensive strategy.