After immigrating to the United States from East Germany as a child, Arnold became disillusioned and turned to life as a street punk. After he was beaten up, he discovered a magazine with an article about Baker training athletes and becomes involved with his program. According to Baker, Arnold has never lost in an official match. Part of this is due to his determination to not want to return to this "hellish" life; however, he loses to Syuusuke Fuji of Seigaku, who incidentally has never lost in an official singles match before at this point during the Goodwill Games. Arnold is called a tennis machine because of his accuracy and the ability to finger out his opponent's shots and countering them.