Cleanup hitter

In baseball, the cleanup hitter is the hitter who bats fourth in the lineup. Although the third man up is generally the hitter with the highest batting average, cleanup hitters often have the most power on the team and are typically the team's best power hitter; their job is to "clean up the bases", hence the name.

The theory behind the cleanup hitter is that at the beginning of the game, at least one of the first three batters will reach base with a single-base hit, walk or equivalent in the first inning, enabling the cleanup hitter a chance to drive in a run. This theory is backed up by sabermetric research, which postulates that the cleanup hitter should be the best hitter on the team with power.

Justin Morneau holds the record of most games started in a season batting cleanup, with 163 in 2008.

In Japan and South Korea, the third, fourth, and fifth batters in a lineup are referred to as "cleanup" (also "cleanup trio").

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