It is a common belief that the team that came up after winning the 5th game of the playoffs (PO) is at a disadvantage in the Korean Series (KS) due to physical depletion.
However, looking at the past KBO League records, there were more cases of 'rebellion' in the Korean Series by teams that made it through the fierce battle in Game 5 than by teams that ended the PO early.
The professional baseball Samsung Lions will play the first game of the Korean Series with 4 wins out of 7 against regular season leader KT Wiz at KT Wiz Park in Suwon on the 3rd.
Samsung won 6-1 in Game 5 of the PO against KIA Tigers held in Daegu on the 1st, won a ticket to the Korean Series with a series record of 3 wins and 2 losses, and then moved to Suwon after resting for just one day.
Objective data points to the overwhelming superiority of KT, the regular season champion.
In the 35 Korean Series based on a single season (excluding the two major leagues since 1989 and 1999-2000), the number of times the team ranked first in the regular season has won 30 times, or 85.7%.
There were only 5 cases out of 35 (14.3%) in which the team that came up through PO defeated the team ranked first in the regular season and achieved an 'upset victory'.
However, when dividing the PO winning teams into 'teams that played until Game 5' and 'teams that finished before Game 5', the probability of winning the Korean Series for the team that went through a fierce battle in Game 5 was about 2.5 times higher than that of the team that passed early.
Among the 35 times in a single season, there were a total of 13 cases in which the PO advanced to the final game of the 5th game with 3 wins and 2 losses.
Among these, three teams, from the 1992 Lotte Giants (4 wins and 1 loss to Binggrae) to the 2015 Doosan Bears (4 wins and 1 loss to Samsung) to the 2018 SK Wyverns (4 wins and 2 losses to Doosan), defeated the top team in the regular season and reached the top of the Korean Series, with a winning probability of 23.1% (3 out of 13).
If we expand the period from 1986 to 1988, when the league was played in the post-war period, to all teams that won 3 out of 5 games and won the 5th PO game (15 times), the 1987 Haitai Tigers (4 wins over Samsung) are added, and the probability of winning increases to 26.7% (4 out of 15).
On the other hand, among the 22 teams (based on a single season) that saved their stamina by finishing the PO early without dragging it to the 5th game, only two teams won the Korean Series: Haitai in 1989 (PO 3 wins, KS 4 wins, 1 loss) and Doosan in 2001 (PO 3 wins, 1 loss, KS 4 wins, 2 losses), and the probability was only 9.1% (2 out of 22).
Among the seven teams that passed the PO with 3 wins and no losses out of 5, only Haitai (14.3%) won in 1989, and among the 12 teams that improved to 3 wins and 1 loss, only Doosan (8.3%) rose to the throne in 2001.
Samsung also got a break by passing the LG Twins and PO with 3 wins and 1 loss in 2024, but was pushed back by 1st place KIA with 1 win and 4 losses in the Korean Series and remained in runner-up.
The team ranked first in the regular season has already rested for nearly three weeks and completely reorganized its strength, so it is difficult for the PO winning team to gain a physical advantage even if the team ends the series one or two games early.
Rather, the short break of the PO winning team only dulled the batters' sense of actual play.
Conversely, the team that won the cliffhanger in Game 5 of PO enters Game 1 of the Korean Series with the players' concentration and batting skills at their peak.
Typical examples include the momentum of heroes born from PO blood feuds, such as Lotte's Yeom Jong-seok in 1992, Doosan's Dustin Nippert in 2015, and SK's Kim Kang-min and Hanyu Seom in 2018, which swallowed up the Korean Series.
Of course, as the 2023 KT and 2025 Hanwha Eagles, the teams that recently won Game 5 of the PO twice, both withdrew from the Korean Series with 1 win and 4 losses, mound fatigue management is still Samsung's biggest task.
