The Chicago Bulls have won six NBA championships in their history, all of which came when Michael Jordan graced the hardwood of the Chicago Stadium and the United Center in the '90s.

Along the way, the Bulls forged numerous heated rivalries that are still remembered today.

Obviously, Chicago got the upper hand most of the time, but that didn't make the matchups with its rivals any less compelling.

Here are the Bulls' top five rivals.

5. Boston Celtics

One of the only teams Jordan was never able to beat.

The Celtics-Bulls rivalry actually began before MJ was even in the league, as they first met in the playoffs in 1981. Boston completed a three-game first-round sweep of Chicago that year, ultimately winning a championship.

Then, Jordan's Bulls matched up with Larry Bird and the C's in back-to-back year in 1986 and 1987, with Bird leading the Celtics to a pair of first-round sweeps.

Bulls-Michael-Jordan-Celtics-Danny-Ainge

That would mark the last time Jordan saw the Celtics in the postseason, but those meetings undoubtedly helped him grow as a player. As a matter of fact, in Game 2 in '86, Jordan scored 63 points in a double-overtime loss to Boston, one of the most memorable performances of his career. It even led to Bird saying that it was “God disguised as Michael Jordan.”

Since then, the Celtics and Bulls have met in the playoffs just twice, with Boston notching a pair of first-round victories in 2009 and 2017. The 2009 seven-game series was one of the more exciting first-round series of all time.

4. Miami Heat

The Heat became an NBA franchise in 1988, four years after Jordan was even drafted.

But Miami has still become one of Chicago's hated rivals.

The Bulls have met the Heat in the playoffs seven times, with the first meeting coming in 1992 and the most recent one surfacing in 2013.

Jordan and Co. made short work of Miami the first two matchups, sweeping the Heat in a couple of first-round clashes. The Bulls then met Miami in the Eastern Conference Finals in 1997, beating Alonzo Mourning's club in a rather non-competitive five-game set.

Those were the only three times the franchises collided in the postseason during MJ's tenure, but they proceeded to meet again in back-to-back years in 2006 and 2007. Miami got the better end of Chicago the first time around, as Dwyane Wade and Shaquille O'Neal led the Heat to a six-game triumph in the first round en route to an eventual NBA championship. The Bulls got revenge a year later, sweeping Miami.

LeBron James, Pat Riley, Heat

Things got heated once again in 2011, when Wade, LeBron James and Chris Bosh ousted a Derrick Rose-led Bulls squad in five games in the Eastern Conference Finals. A couple of years later, James and the boys beat Chicago in a five-game second-round series.

3. Cleveland Cavaliers

Most young fans probably don't remember this, but early on in Jordan's career, the Cavaliers were one of the main obstacles he and the Bulls faced.

Cleveland was also on the wrong end of one of the biggest highlights of Jordan's NBA tenure, as he hit an incredibly difficult shot over Craig Ehlo in the 1989 playoffs to complete a 3-2 series victory (it would simply become known as “The Shot”).

Overall, the Bulls met the Cavs in the postseason a hefty five times between 1988 and 1994, with Chicago emerging victorious each meeting. While the last two meetings were Bulls sweeps in '93 and '94, the first three clashes were very competitive, as Chicago and Cleveland went the distance in the first round in both '88 and '89 and had a six-game battle in the conference finals in 1992.

Since then, the Cavs and Bulls have collided twice in the playoffs, with LeBron leading the Cavs to a pair of wins in 2010 and 2015.

At this point, the rivalry is all but dead, but back in the day, it wasn't the playoffs without a Bulls-Cavs series.

2. New York Knicks

Yes, this rivalry is pretty one-sided, as the Bulls have won six of the seven playoff meetings between the two sides, but Chicago and New York featured some of the most memorable battles of the '90s.

It actually began in 1981, three years before Jordan was even drafted. As a matter of fact, it was so long ago that at that time, the first round of the playoffs was a best of three. The Bulls “swept” the Knicks that year, beating them 2-0.

The first playoff meeting of Jordan's Bulls versus Patrick Ewing's Knicks then occurred in 1989, when Chicago topped New York in six games in the second round. Then, between 1991 and 1996, Chicago and New York met five more times, with the Bulls coming out in top in four of those clashes.

Charles Oakley, Patrick Ewing, Knicks

The only time Chicago didn't beat the Knicks during that span? In 1994, when Jordan was retired.

The type of physical basketball we saw in these postseason matches just does not happen today. As a matter of fact, some of the things that Charles Oakley and Anthony Mason used to do to Jordan and Scottie Pippen are not even legal in today's NBA.

Any time you mention '90s basketball to someone who was around at the time, the classic matchups between the Knicks and Bulls on NBC are among the first things that will come to mind.

1. Detroit Pistons

I don't think there is a team that Jordan hated more than the Pistons.

Whether it was his fierce and everlasting rivalry with Isiah Thomas or his disdain for Bill Laimbeer, Rick Mahorn and Detroit's physical frontcourt, Jordan despised the Bad Boy Pistons.

Early on, it didn't look like the GOAT would ever beat Detroit, as the Pistons bounced him and the Bulls from the playoffs three straight years between 1988 and 1990.

Isiah Thomas, Pistons, Bulls

But then, in 1991, the tide turned, when Jordan led Chicago to a four-game sweep of Detroit in the Eastern Conference Finals, ending the Pistons' reign and beginning a dynasty of his own.

The Bulls went on to win the title in '91 and collected three straight championships between '91 and '93, establishing one of the greatest runs we have ever seen in NBA history.

Chicago and Detroit have only met in the playoffs once since, with the Pistons topping the Bulls in six games in 2007, but the memories from those early battles will never fade.