Fourth outfielder

In baseball, a fourth outfielder is a backup outfielder, who does not have the hitting skills to regularly play in the corner outfield, but does not have the fielding skills to play center field; for these players, this often leads to playing time that has been called "erratic and unpredictable". Often, fourth outfielders are outfield prospects who have not settled on one outfield position when arriving in the Major Leagues, veteran players seeking additional playing time to extend their careers, or part-time position players who double as designated hitters.

A current example would be Gerardo Parra of the Milwaukee Brewers. Considered among the best defensive outfielders and a Rawlings Gold Glove Award winner in 2011, Parra was employed among all three outfield positions during the 2012 Major League Baseball season.

In contrast, the term fifth infielder does not refer to a backup or reserve infielder, but to a defensive shift where a fielder from the outfield is brought into the infield, leaving a team with only two players in the outfield.

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