One of the unique aspects of MLS is the wide variety of its teams, and subsequently, their rivalries. Some are new and some are old. Some involve teams from the same city, while others cross borders (and not just states, but countries). There exist rivalries between fan bases with different languages, teams with drastically different playing styles, and cities of different milieus, climates and elevations.

But if there’s one thing that the following rivalries have in common – aside from being composed of clubs that don't seem to like each other very much – is that they’re the most underrated of the bunch.

4) New York City FC vs. Orlando City SC

New York City and Orlando made their MLS debuts against each other back in 2015 and the game was a memorable one: a 1-1 draw with drama and craziness – a crowd of more than 60,000, two late goals, six yellow cards and a red. It felt like the beginning of something special. And it was.

In their third season, the two teams provide some of the most intriguing and fiercely contested games on the MLS calendar. It helps that coach Jason Kreis is now in his first full season in charge at Orlando – after being fired by New York City at the end of the expansion campaign. It’s clear that for Kreis, playing against New York isn’t just any other game; and perhaps the same goes for Patrick Vieira, who replaced him at the helm. The two teams have already played each other three times this year and each game has had plenty of intensity and talking points, especially when Vieira claimed that his team had played better than Orlando in all three games, despite the fact that Orlando had won the first two meetings. Kreis didn’t appreciate those comments, and a war of words ensued. The next time these two teams meet might well be the playoffs, and that’s not something you’ll want to miss.

3) FC Dallas vs. Houston Dynamo

Of the in-state rivalries, the Texas derby deserves more attention than it gets. Maybe it won’t garner the same kind of fanfare that other rivalries will, but the animosity between the teams is just as high. This might only be one incident, but go have a look at Ricardo Clark kicking Carlos Ruiz in the chest in 2006.

The sporting rivalry between Big D and Space City goes back a long time and spans several sports. The MLS version is more than a decade old – and the Dynamo have had the better of things so far, winning consecutive MLS Cups in 2005 and 2006. That hasn’t sat so well with Dallas, who have yet to win a title, despite being around since the league's inception (though perhaps that changes this year …)

These two have played many memorable games against each other. And now that Dallas and Houston are among the top sides in the West, and have some of the league’s most exciting attacking players, you might be hard-pressed to find a better fixture to watch. To top it all off, the winner of the overall meetings during a season claims El Capitan: a mountain howitzer cannon.

2) Seattle Sounders vs. Vancouver Whitecaps FC

Seattle vs. Portland deserves much of the hoopla it gets, but what about another Cascadia derby? Seattle vs. Vancouver doesn’t get as much notice as it should. Sure, there’s also Vancouver vs. Portland, which might be more intense in some ways, but Seattle vs. Vancouver has plenty of bite and lots of traveling fans too. Most importantly, it not only has the longest history of the three Cascadia rivalries, it’s the oldest rivalry in North American soccer, period, dating back all the way to 1974. That’s something that needs to be cherished and celebrated more.

And what makes the rivalry extra special this year is that the Whitecaps’ signed former Seattle star Fredy Montero, much to the Sounders’ supporters displeasure. It’s been a slow start to the season for Montero, who notably opted against celebrating earlier this year, but he has plenty of time to get his sporting boots on before the next time Vancouver faces Seattle, which will be on August 23 at BC Place. The 'Caps travel to visit the Sounders on September 27.

1) Montreal Impact vs. Toronto FC

If this is the most underrated rivalry, it’s in part due to a reluctance to explain the reasons for why it’s so heated. “What people think, we dare say out loud,” read one banner on Wednesday at Stade Saputo, when the Impact hosted TFC in the first leg of the Canadian Championship – a 1-1 draw. I won’t however spell out what the fans did finally dare say, but what I will say is that this rivalry is fierce; from an emotional standpoint, the fiercest team sporting event in Canada. Was anyone really expecting TFC, on the equalizing goal, to kick the ball out with an injured Montreal defender in the box calling for medical attention? Fat chance that was ever going to happen. You won’t find any of your customary Canadian friendliness here.

Seattle-Portland aside, this is the best rivalry in MLS. The sporting rivalry between the two cities goes back more than 100 years and the political antagonism goes much further. Comparisons between the two teams are always being made and they seem to be keeping a close eye on what each other's up to. Impact get Italian DPs; Toronto gets an Italian DP. Toronto has success with a back three; the Impact start playing with a back three. Coincidence? Je ne pense pas. I could go on.