Through a combination of numerous injuries, a weak frame, and financial difficulties, the protagonist Jinyong Lee gave up on his path to being a baseball athlete and lived as a factory employee instead. One day, the spirit of Jinho Kim, the baseball hero who was hailed as a legend in Korea, as well as Jinyong Lee's idol who passed away 10 years ago, appeared before him. At the same time, an unknown notice appeared, stating that the "Baseball Manager" would start, and Jinyong Lee gained an ability that gave him the constitution of a pitcher, similar to a game avatar. He returns to the field to become "King of the Mound."