Baseball at the 1988 Summer Olympics was a demonstration sport for the seventh time. It would become an official sport 4 years later at the 1992 Summer Olympics. Eight teams competed in Jamsil Baseball Stadium in the baseball tournament. The format used was the same as the tournament of four years earlier. Five teams that had competed in the 1984 tournament returned. Cuba originally qualified but withdrew as a result of the boycott.
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There were two pools for the preliminary round. Teams played each of the three other teams in their division.
The semifinals pitted the first-place team of each division against the second-place team of the other division. Thus, Japan (3-0) played against Korea (2-1), which had a tied record with the United States (2-1) but had lost in head-to-head competition against them. The first-place Americans played against Puerto Rico (2-1).
The third-place final pitted the losers of the semifinals against each, with the winner taking third place and the loser taking fourth.
The winners of the semifinals played each other for first and second place. In a rematch of the 1984 final, the reigning champion Japanese team lost to the United States. Since baseball was a demonstration sport, no official medals were awarded.
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