Closer Lee Sang-Yong(2013)

Lee Sang-yong has been pitching for the Gators' second team for 10 years. He is a man who thoroughly understands his routine and plans out his moves every day.
However, no matter how well he manages himself, he is a late-life second-tier player who never got a chance.
He has good stats, with ERA in the 3's for the second team over 10 years, which is worthy of a spot on the first team.
But the manager and coach never called him up, because his pitches are slow.
Pitchers who throw hard are always called promising prospects no matter what, and they get more opportunities thanks to unfounded expectations that they will one day explode with potential. However, players with slow pitch speeds are never given such an opportunity.

Jin Seung-nam is the second-team catcher for the Gators.
He is a big man with a bright and generous personality, who never lets anything get in his way.
He is the type of player who plays baseball instinctively with an intuitive game sense. However, for him, the situation with the Gators organization is becoming a big obstacle.

Lee Sang-yong decides to seize the opportunity by creating synergy working with Jin Seung-nam.
To do so, he begins to teach Jin Seung-nam the nuances of baseball strategy and the proper way to play…

(Source: KakaoPage, translated)