Fielding team

The pitcher's main role is to pitch the ball toward home plate with the goal of getting the batter out. Pitchers also play defense by fielding batted balls, covering bases (for a potential tag out or force out on an approaching runner), or backing up throws. The catcher's main role is to receive the pitch if the batter does not hit it. Together with the pitcher and coaches, the catcher plots game strategy by suggesting different pitches and by shifting the starting positions of the other fielders. Catchers are also responsible for defense in the area near home plate.

The four infielders are the first baseman, second baseman, shortstop, and third baseman. The first and third basemen play near their respective bases. The second baseman and the shortstop position themselves in the gaps on either side of second base, toward first and third base, respectively. Originally, the second baseman played very close to second base; this positioning shifted when teams found it necessary to have four infielders, rather than four outfielders. The first baseman's job consists largely of making force plays at first base on ground balls hit to the other infielders.

The first baseman also fields balls hit near first base, but because the position is less demanding than the others, the team's strongest hitter is often also their first baseman. The second baseman covers the area to the right of second base and provides backup for the first baseman. The shortstop fills the critical gap between second and third bases—where right-handed batters generally hit ground balls—and also covers second or third base and the near part of left field. This position is the most demanding defensively, so a good shortstop need not necessarily be a good batter. The third baseman's primary requirement is a strong throwing arm, in order to make the long throw across the infield to the first baseman. Quick reaction time is also important for third basemen, as they tend to see more sharply hit balls than the other infielders.

The three outfielders are called the left fielder, the center fielder, and the right fielder, the positions being named from the catcher's perspective. The center fielder has more territory to cover than the corner outfielders, so this player must be quick and agile with a strong arm to throw balls in to the infield; as with the shortstop, teams tend to emphasize defense at this position. Also, the center fielder is considered the outfield leader, and left- and right-fielders should cede to his direction when fielding fly balls.

The locations of the fielders are not specified by the rules. Players often shift their positioning in response to specific batters or game situations, and they may exchange positions with one another at any time.