(from ebookjapan):

Despite his extraordinary talent, Go Habara, a member of the Giants' baseball team, has fallen into an extreme slump due to illness.

As a way to rest, Habara visits a bat factory in Aizu Wakamatsu, where his sister, Tamie, has married, and asks her husband, Jotaro Nanjo, a bat craftsman, to make a new bat for her. Later, Tamie returns to Tokyo with her son Hayato in her arms to deliver the bat, but Habara is already on his deathbed.

Tamie heads for the hospital, but on the way there, she is involved in a traffic accident and is buried. Fortunately, Hayato survived. Three years later, Jotaro took Hayato with him to Tokyo to make a name for himself as a bat craftsman.

Another early popular work of Weekly Shonen Jump.