Mario Incandenza, Sr. 

He is James’s grandfather, the father of James’s father. He is a golf addicted Green Valley, Arizona oculist who doesn’t support James’s father. Mario, Sr. only attends one of James’s father’s tennis matches, and it is the one where James’s father faces the son of the one of Mario, Sr.’s clients. During the match, Mario, Sr. claims that his son is good, but will never be great. 

 

James’s Grandmother

She is James’s grandmother, the mother of James’s father. She always comes to all of James’s father’s tennis matches, therefore making her presence almost always means nothing to him.

 

James’s Great Uncle

He is the great uncle of James who electrocutes himself with a field series generator that he wants to patent.