Akira Sendoh is a prominent character known as the ace of Ryonan High School's basketball team. He is a seventeen-year-old student in his second year of high school, standing 190 centimeters tall and weighing 79 kilograms. He was originally from Tokyo, where he attended Kitazawagakuen Junior High, before being recruited to attend school in Kanagawa Prefecture. His jersey number is 7.

Sendoh is widely recognized for his calm, confident, and easygoing personality. Unlike many intense competitors, he has a relaxed and sometimes even lackadaisical demeanor, a trait that is famously illustrated by his habit of arriving late to practices and games, often with the simple excuse of having overslept. He frequently wears a slight, almost disarming smile, which contributes to his approachable and friendly nature. Despite his popularity and the respect he commands, he can appear somewhat detached or difficult to truly know, as his inner world seems to be one of great personal calm. His primary hobby outside of basketball is fishing, a solitary activity that reflects his need for peace and relaxation away from the intensity of competitive sports.

On the basketball court, Sendoh transforms into a formidable and strategic player. He is a prodigious talent, often referred to as a "genius" and was considered the "Rookie King" in his first year of high school, a title that drew comparisons to the prodigy Rukawa Kaede. His skill set is exceptionally well-rounded, earning him a spot as one of the top five players in the Kanagawa prefecture. While his natural position is small forward, he is also highly effective as a point guard, showcasing his incredible basketball IQ and versatility. Coach Taoka of Ryonan utilized this versatility to restructure the team's offense around him. He is a proficient scorer, rebounder, and defender, but his most distinguishing ability is his exceptional court vision and strategic mind. He can control the flow of a game, and his passing skills elevate the performance of his entire team.

Sendoh's role in the story is primarily as a rival and a benchmark for other key characters. He is a major obstacle for Shohoku High School, and his matches against them are pivotal. For the intense and talented Rukawa Kaede, Sendoh represents a rival who is slightly out of reach, someone whose well-rounded game and cool-headed strategy present a challenge that pure scoring ability cannot overcome. A late-night one-on-one game between them ended in a draw, after which Sendoh offered Rukawa advice on broadening his offensive perspective. He also takes note of the raw, untrained athleticism of Hanamichi Sakuragi, recognizing his potential long before most others, and even playfully provokes him. His rivalries extend to the top players in the region, such as the powerful Maki Shinichi of Kainan. Their head-to-head battles are legendary, and after a close loss, Maki shook Sendoh's hand in a gesture of deep respect, acknowledging him as an equal.

Throughout the series, Sendoh demonstrates a subtle but significant development in his approach to basketball. As an underclassman, he was a scoring machine, much like Rukawa, capable of single-handedly putting up massive point totals. However, as a second-year player, he evolved into a more complete team player, finding that the strategic challenge of setting up his teammates and controlling the game's tempo was just as satisfying as scoring. This change made him a more dangerous and unpredictable opponent. Although his team lost its chance to compete in the national championships, his leadership was never in question. He is often described as the team's true captain, even before officially assuming the title, because of his ability to unify and calm his teammates under pressure. Following the retirement of the team's captain, the center Uozumi Jun, Sendoh is expected to take over as the new leader of Ryonan.