The captain who led the weak Powerful High School to Koshien. Drafted first overall by the struggling Ganbare Powerfuls, he led them to a league title and earned the nickname "Mr. Powerfuls." A true genius with monstrous hitting power, defensive skill, and speed, capable of playing every position. Main position: Shortstop. First person: I (casual/masculine). Joined the Powerfuls out of admiration for Koba. He believes pro baseball players should be "absolute heroes" who give dreams to children. He views his abilities not as something gained through "spending an eternity training," but through "spending an eternity enjoying the sport of baseball." He is Mamoru Ikari's rival and Susumu Ikari's friend. He has a lovely wife named Mai. He is quite dense regarding romance and says "I like you" easily, but only says "I love you" to Mai. Despite his achievements, he is actually quite timid, faint-hearted, and humble. Though he has matured, he was originally someone who lacked self-confidence. He was hospitalized after getting into a traffic accident while protecting the protagonist.

First person: I (Oira). Ends sentences with "-yansu." An otaku who loves anime like Gander Robo. Transferred to the Powerfuls from the Nippon-Ham Fighters a year ago. Was a regular at Powerful High School during the same era as Konami. Konami's one and only best friend. Possesses the mysterious skill of instantly producing a futon and pillow to sleep anywhere(?). A bit of a klutz. A fast-running outfielder.

The cleanup hitter for the Powerfuls. Possesses absolute hitting power that even Konami cannot surpass. He was the original "Mr. Powerfuls" before Konami earned the title. Realizing the team he once admired and fought for has become a "collection of slackers," he is currently a free agent in talks with multiple teams. This indecision has caused his performance to slump, failing to hit in crucial moments. A true "man's man."

A pitcher for the Powerfuls, drafted first overall. Speaks with a regional drawl (Kansai). Possesses incredible observational skills, memorizing every player's form and habits to report to the manager and help correct them (kept secret from everyone but the manager). Used to consistently rank first in national mock exams. In school, he was called "Grind-boy" because he was small and weak. A pleasant guy who never stops smiling and always says "Thanks a bunch!" A pitcher who prides himself on a variety of breaking balls and high control. However, compared to other aces, he lacks a standout quality, leading to rumors that he only gets play time by sucking up to the manager.

First baseman for the Powerfuls. While his contemporaries like Hashimori have become managers, he remains active as a player. Holds 214 multi-hit games (2nd all-time). Has a soft-spoken and kind personality. Due to age-related decline, thoughts of retirement crossed his mind when he hit his 200th multi-hit game. He has a son named Nao who is in elementary school. Nao is being excluded by his peers because Koba has been striking out frequently.

The absolute ace of the Kaisers. Left-handed pitcher and hitter. Extremely confident, calling himself a genius and top-tier. He has the skill and results to back it up, but he is snobbish, prideful, and hates losing. Was the ace of Akatsuki High. In the regional finals, he lost to his rival Pawapuro's Powerful High School. Shows a tsundere side. As he ages, he has begun to show a more honest side, growing as a person by acting as a role model for the next generation. While calling himself a genius, he subjects himself to grueling training behind the scenes. His motto: "Genius is 1% talent and 99% effort." Uses an original fastball called the "Rising Cannon."

Mamoru Ikari's younger brother and the starting catcher for the Kaisers. In contrast to his brother, he is a mild-mannered and polite young man. Right-handed pitcher, left-handed hitter. In high school, he was involved in a traffic accident while going out with his friend Pawapuro and was unable to compete in the tournament. Likes cat cafes and sweets. Talented enough to be the starting catcher for his older brother. However, he remains humble and works hard. Respects both Pawapuro and his brother.

Pitcher for the Cat Hands. The first female pro baseball player. Right-handed sidearm pitcher. She lacks speed but excels in control and breaking balls. Can use an original breaking ball called "Marine Splash" that curves like a sinker. First person: I (soft/polite). Called "Erlenmeyer Flask" (due to her wide hips). Was the pitcher for Renren High School and was close friends with the captain, Konami, forming a battery. She has been friends with Konami since school and fought him in official tournaments. She is worried about the hospitalized Konami.

A flight attendant. A fan of the Powerfuls. Specifically, a huge fan of the protagonist, having watched him since his minor league days. Has a twin sister named Umi. She cherishes Umi deeply as they lost their parents in an accident. Has a strong personality and won't hesitate to slap anyone who mocks the protagonist. Shy only around the protagonist. Extremely cute!

Manager of the Powerfuls' first-string team. A former player who supported the Powerfuls during their golden age. Nicknamed "Hot-Blooded Full Swing."