The third baseman positions himself in the vicinity of the third-base bag, facing home plate with the base in front of him and to the right.
On defense: Third basemen are responsible for fielding ground balls, line drives and pop flies in the general vicinity of the third-base bag. They ideally possess strong, accurate arms with which to throw across the diamond and quick reaction times given their close proximity to home plate. Notably, third basemen must also be prepared to field bunt attempts, as batters will often bunt the ball down the third-base line in sacrifice situations or in an attempt to record a "bunt base hit" in surprise fashion.
Third basemen typically have less ground to cover than the shortstop playing beside them and therefore tend to possess less lateral range.
On offense: Although third base is a more premium defensive position than first base -- baseball's other corner-infield spot -- a good defensive third baseman is still easier to find than a good defensive shortstop or catcher. As a result, third basemen are often required to produce in above-average fashion on offense. In fact, many third basemen possess a good deal of power. In 2015, 11 third basemen hit at least 20 home runs. By comparison, just two shortstops hit at least 20 homers that year.