A player steals a base when he challenges the defense by advancing to the next base without the ball being hit by a teammate. Players can steal anytime they think they can make it to the next base without the defense tagging them out.
Players usually steal while the pitcher is delivering the ball to home plate, trying to make it to the next base before the catcher can receive the pitch and throw to the base.
Because second base is farther from the catcher than third base, most steals take place at second. On rare occasions, a player steals home, attempting to slide in safely before the catcher receives the pitch and can make a tag.
A double steal is when two players steal at once. It most often occurs with runners at first and third base. The runner on first breaks to steal second, and when the catcher throws to second, the runner at third breaks for home.
Sometimes the defense counters a double steal by having the shortstop or second baseman intercept the throw from the catcher before it reaches second base. The infielder then fires it home before the runner on third can arrive safely.
Taking an Extra Base
A player is said to be taking an extra base on a hit when he advances one more base than the hit itself would guarantee.
For example, a runner on first takes an extra base by going all the way to third when a teammate hits a single to right field, because the single normally advances the runner only to second.
When a batter hits a double, the runner on first takes an extra base by coming home to score rather than stopping at third.
Tagging up is a way for a runner to advance a base when an out is made. A runner can tag up only on a fly ball caught with less than two outs.
He must wait until the ball is touched by the outfielder before leaving his base and running to the next one.
Most players only tag up on balls hit fairly deep to the outfield, because otherwise the fielder is closer to the infield and his throw will come in quicker.
If a runner scores after tagging up, the hitter’s out is recorded as a sacrifice fly, and the hitter is awarded a run batted in (RBI).
There are two ways of sliding, headfirst and feetfirst. The headfirst slide is quicker to the base because the runner stretches his body, extends his arm, and reaches as far as he can.
The feetfirst slide is more conventional, but the runner does not reach the base as quickly because he has to bend his knee to absorb the impact of hitting the base.
The feetfirst slide makes it easier for the runner to break up double plays and knock the ball out of the fielder’s glove. It is also less likely to result in injury; jamming the hand or fingers is easy when sliding headfirst.