Three Moments That Shaped Boston Celtics History on September 21

A Date Etched in Green and White

September 21 is a date that carries surprising weight in Boston Celtics history — touching on a Hall of Fame career, a quiet farewell to one of the franchise's early pillars, and one of the most shocking front-office scandals the NBA has ever seen. From a Florida-born giant who became one of basketball's most efficient scorers, to a coach who went from championship contender to persona non grata in the span of a single offseason, this date tells a layered story about the Celtics across multiple eras.

The A-Train Turns 77

Today in Celtics history, Artis Gilmore was born in the small southern town of Chipley, Florida, in 1949. He would grow into one of the most physically dominant players the sport has ever produced. After playing five seasons in the ABA — winning Rookie of the Year and MVP in 1972, earning All-Star and All-ABA First Team honors all five seasons, and winning four rebounding titles — Gilmore was the first overall pick in the 1976 ABA Dispersal Draft.

During his 12-year NBA career with the Bulls, Spurs, and a brief stint with the Celtics, the 7-foot-2 center known as the "A-Train" was a six-time NBA All-Star, amassing 15,579 points, 9,161 rebounds, and 1,747 blocks in 909 career games. His 59.9 career field goal percentage remains the top mark for any player averaging over 10 shots per game. He joined the Celtics as a free agent in 1988, playing 47 games for Boston in the 1988-89 season and averaging 3.5 points and 3.1 rebounds per game — a quiet coda to a legendary career. Gilmore was inducted into the Naismith Memorial Basketball Hall of Fame in 2011.

Remembering Bob Donham

September 21 is also the anniversary of the passing of Bob Donham, who died on this date in 1983 in Seattle, Washington, at the age of 56. Donham was one of the franchise's earliest contributors, a steady and reliable presence during the Celtics' formative years. Born in Hammond, Indiana in 1926, Donham was drafted out of Ohio State by the Celtics in the 1950 NBA Draft. He played four seasons with the team — the entirety of his NBA career — averaging 6.7 points, 3.9 rebounds, and 2.6 assists per game.

After his playing career ended, Donham became the junior varsity basketball coach at the University of Washington, where he was working on his doctorate in physical education. In 1957, he became the head coach at Bowdoin College, before resigning in 1962 to enter the securities business. He may not be a household name today, but Donham helped lay the groundwork for a dynasty that would go on to win banner after banner.

The Udoka Scandal That Rocked Boston

September 21 is also the date that news of Celtics coach Ime Udoka's improper relationship with a female staffer broke in 2022, setting in motion a turbulent end to Udoka's relationship with the team. The timing was brutal — training camp was days away and the Celtics were widely considered title contenders. Udoka had finished his first season with a brilliant 51-31 record, leading Boston past Brooklyn, Milwaukee, and Miami on the way to the NBA Finals, where the Celtics ultimately lost to the Golden State Warriors in six games.

Udoka was suspended by the team and did not coach in the 2022-23 season. The Celtics officially cited "violations of team policies," with multiple reports indicating the violation involved an improper intimate relationship with a Celtics staff member. Suspended indefinitely, then-assistant Joe Mazzulla took on the role of interim head coach just days before training camp, and Udoka and Boston would agree to part ways permanently later that season. Mazzulla, thrown into the fire under extraordinary circumstances, ultimately guided the Celtics all the way to an NBA championship in 2024 — a remarkable silver lining to one of the franchise's darkest off-court moments.

Three very different stories, one shared date. The Celtics' history is as rich and complicated as any franchise in professional sports, and September 21 captures that complexity perfectly — celebrating greatness, mourning loss, and confronting hard truths all at once.