Daichi Sawamura captained Izumitate Junior High's volleyball team alongside Hayato Ikejiri and Yui Michimiya. In a tournament match against a powerhouse team, he chased every ball relentlessly despite teammates losing hope, though they lost. This defeat cemented his belief that victory requires self-confidence, a philosophy he later reinforced to Ikejiri. The pair vowed to continue volleyball and reunite on the court, leading Daichi to enroll at Karasuno High for its historic volleyball program. As a Karasuno first-year, he naturally led peers Sugawara Koushi and Azumane Asahi, initiating extra training, researching tactics, and recruiting manager Shimizu Kiyoko to stabilize the declining team. By third year, he rose to captain and wing spiker (jersey number 1), characterized by a muscular build, short dark hair, and an intimidating presence when angered. His mature demeanor often masked his age, though childish flashes surfaced, like accidentally triggering an emergency bell during a lunchtime scuffle. He prioritized team unity and discipline. After witnessing first-years Kageyama Tobio and Hinata Shouyou argue during recruitment, he barred them from club activities until they cooperated. Later, he staged a 3-on-3 match to test their compatibility, strategically opposing them to observe dynamics. His leadership extended off-court when Hinata and Kageyama failed exams, threatening their Tokyo training camp attendance; he confiscated their answer sheets and mobilized Yachi and Ennoshita as tutors, stressing collective consequences to emphasize shared responsibility. Defense anchored his playstyle, with high-level receiving skills (rated 4/5 in technique and game sense) steadying Karasuno. He covered teammates' errors and directed formations, notably against Johzenji High. While addressing immediate needs, he envisioned long-term growth, believing Karasuno could become a "perfect volleyball team" and reach nationals. He advocated refining risky techniques like the "freak quick," arguing stagnation would stifle progress against elite opponents. Post-graduation, he joined the Miyagi Prefectural Police's Community Safety Division. His appearance shifted slightly, featuring longer hair styled like former coach Ukai Keishin. A recurring dream involving the vice-principal's wig—referencing its accidental landing on his head during a Hinata-Kageyama altercation—persisted as a personal idiosyncrasy.