The two teams have the most meetings in the NBA playoffs, playing each other in 22 series (and the 1954 Eastern Division Round Robin), with the Celtics winning 15 of them.

Shortly after the All-Star break in 1965, the Sixers acquired Wilt Chamberlain from the Warriors, bringing the Chamberlain/Russell matchup back into the rivalry as well.

With 5 seconds left and Boston leading 110–109, Russell tried to inbound the ball when it hit a guy wire that supported the backboard, which resulted in a turnover.

However, the Sixers failed to capitalize when Celtics forward John Havlicek deflected the inbound pass to Sam Jones, who ran out the clock.

The Celtics advanced to the NBA Finals and defeated the Los Angeles Lakers in five games for their seventh straight title.

[9] In the 1966 season, the Sixers looked poised to end Boston's 7-year reign as NBA Champions; Philadelphia won the regular season series against Boston 6–4 and finished 55–25 to beat out the Celtics by one game and win the number one seed in Eastern Division.

Hannum had also coached the Bob Pettit-led St. Louis Hawks to the 1958 NBA Championship-the last year someone had defeated the Celtics in the championship.

The only two years Russell's Celtics did not win the championship, they lost to teams coached by Alex Hannum.

They became a contender in the East, and in Erving's first season with the team, the Sixers eliminated the defending champion Boston Celtics in a tough seven-game Eastern semifinals in 1977.

Boston slumped for the next two seasons while Philadelphia continued to be a strong team in the NBA, but in 1978, the Celtics drafted Indiana State forward Larry Bird in the hope of reviving their glory years as a franchise.

The next season, both the Celtics and the Sixers finished with the best record in the NBA at 62–20, but Boston held the tiebreaker in the ranking.

The "highlight" of this era of the rivalry was a 1983 exhibition game that featured 3 separate fights: Moses Malone/Cedric Maxwell, Larry Bird/Marc Iavaroni, and Gerald Henderson/Sedale Threatt.

Game 5 saw Larry Bird pick off Andrew Toney with a few seconds left and Boston up by 2, then dribble up court to preserve the Celtics' close victory, reminiscent of John Havlicek's series-clinching steal in 1965.

The Sixers saw a steep decline through the rest of the '80's, trading Malone and Cheeks along with the retirements of Erving and Toney.

Charles Barkley emerged as the Sixers new leader and a prominent NBA superstar, however he was not able to get the team past the second round.

The Celtics won 4–1, and Joel Embiid afterwards remarked "This is not a rivalry, I don't know our record against them, but it's pretty bad.

[17] The teams met again in the 2023 Eastern Conference Semifinals and, despite the 76ers being up 3–2 going into game 6, the Celtics managed to come back and won 4–3.

He also scored a team-high 33 points in the classic Game 7 of the 1982 Eastern Finals in Boston (the famous "Beat LA!"

Bill Russell makes his debut for the Celtics.Celtics win the Eastern Division for the first time.Celtics finish with the best record in the league (44–28).

On March 3, 1960, Nationals beat the Celtics 149–108, their largest victory over the Celtics as a Syracuse team with a 41-point differential and second largest victory overall against them.Celtics win the Eastern Division.Celtics finish with the best record in the league (59–16).Celtics win 1960 NBA Finals.