As one of the most successful and historic franchises in NBA history, the Boston Celtics are bound to have gained some rivals since their founding in 1946. With that being said, some teams have separated themselves from the rest of the pack as the Celtics biggest rivals in the past seven-plus decades.

5. Detroit Pistons

Boston's rivalry with Detroit isn't much of one nowadays, as the Pistons have made the playoffs twice in the last 11 seasons. However, back in the 1980s, the Eastern Conference battles between Larry Bird and Kevin McHale versus Isiah Thomas and the “Bad Boy” Pistons were some of the most heated battles in recent memory.

From 1985 to 1991, the Pistons and the Celtics met in the playoffs a total of five times — two of which came in the Eastern Conference Finals. Boston owns a 5-3 record against Detroit in all-time playoff series with the most recent being in the 2008 ECF.

4. Miami Heat

This rivalry is definitely more recent. While the Celtics and Heat of today don't hate each other too much, go back about a decade and the hate is clearly there. The rivalry especially blew up when LeBron James — who struggled to get past the Celtics Big 3 with the Cleveland Cavaliers — took his talent to South Beach.

As the Celtics' core began to age, LeBron and the Heat were finally able to get past Boston. While Boston holds a 75-47 regular-season record against Miami, the Heat have the edge 9-8 when it comes to the playoffs.

3. New York Knicks

Again, the Celtics and Knicks don't have much of a rivalry anymore, with the Knicks in rebuilding mode for the better part of a decade. However, New York and Boston teams will always have some hostility towards each other and this is no different.

Going back all the way to 1951, these two teams have met in the postseason on 15 separate occasions with Boston holding a narrow 8-7 edge. The rivalry has clashed in postseason play in every decade except for the 2000s, and if New York can back to competing, we should be seeing more of it in the 2020s.

2. Philadelphia 76ers

Starting with the Bill Russell versus Wilt Chamberlain battles of the 1960s, moving to Dr. J versus Bird in the early 80s and now being revitalized in recent playoff series, the Celtics and 76ers have met a total of 555 times.

The rivalry hit a bit of a lull in the 1990s and 2000s but with the two teams back in contention, there's no doubt that these two teams are having a rivalry revival.

1. Los Angeles Lakers.

This one is obvious. Not only are the Lakers the Celtics' biggest rivals, the Celtics/Lakers rivalry is the biggest and most storied in all of the NBA. The rivalry between these two teams is so big and well known that it even got its own ESPN 30 for 30 documentary, Celtics/Lakers: Best of Enemies.

These two teams have met in the NBA Finals an astounding 12 times with Boston holding a commanding 9-3 advantage. Still, as the two most successful franchises in NBA history, there's no love lost when these two teams face off.

Ten of those 12 Finals series went at least six games and the rivalry still lives on today with Los Angeles and Boston both currently near the top of their respective conferences in the halted 2019-20 NBA season.