Second base, or 2B, is the second of four stations on a baseball diamond which must be touched in succession by a base runner in order to score a run for that player's team. A second baseman is the baseball player guarding second base. Also called 2B, or second bagger, the second baseman often possesses quick hands and feet, needs the ability to get rid of the ball quickly, and must be able to make the pivot on a double play. In addition, shortstops and second basemen are usually right-handed as this is preferential for turning a double play. Second base is also known as the keystone sack. In the numbering system used to record defensive plays, the second baseman is assigned the number 4.
Second basemen must be quick on their feet to hold the runner on base, back up the shortstop on all throws from the catcher, cover first base on bunted balls, and to field the position to either side. Good second basemen need to have very good range, since they have to field balls closer to the first baseman who is often holding runners on, or moving towards the base to cover. Good range is also helpful since many balls are hit to this position. On a batted ball to right field, the second baseman goes out towards the ball for the relay. Due to these requirements, second base is sometimes a primarily defensive position in the modern game, but there are hitting stars, too.
For baserunners, second is the easiest base to steal, because the catcher must throw a farther distance.