Boston and Montreal. Edmonton and Calgary. New York and New Jersey. Philadelphia and Pittsburgh. Detroit and Chicago.
I think you get the idea. Rivalries are the greatest source of drama in sports, and hockey's are almost entirely northern, eastern, or both. Even more recent rivalries have some basis in the game's most traditional markets.
The problem with most burgeoning rivalries in the league's non-traditional markets is that the teams have struggled to stay consistently good at the same time. In California alone, 2013 was the first time all three teams made the playoffs in the same season.
St. Louis made the playoffs a zillion years in a row while teams like the Kings were doormats. Colorado and Dallas were very competitive at the same time, but their paths only crossed twice. Those series may have been excellent, but the two teams weren't in the same division and lacked geographical proximity. I don't think those things aren't entirely necessary, but they do help drive competition. At the very least, they drive animosity between fans, especially with the way the NHL has been structured since expansion in the early '90s.
So, proximity, divisional competition, quality of team. Those are all things that matter. What else? Repeated playoff matchups are a must. Bad blood between the teams for sure. Some kind of interconnected roster movement definitely helps.
What teams are we looking at, anyway? Some people refer to these franchises as the Sunbelt, but I'm not sure exactly what that entails. San Jose isn't close to the same as places like Phoenix and Atlanta and Tampa Bay. St. Louis isn't exactly a traditional market, but it also doesn't fall in line with the Sunbelt or San Jose. I'm still interested in including them, even if it is a bit of a reach.
I settled on 11 teams, not counting the hapless Atlanta Thrashers: Kings, Sharks, Ducks, Coyotes, Stars, Avalanche, Blues, Predators, Panthers, Lightning, Hurricanes.
If you pluck any 11 teams out of the NHL at random, you should be able to come up with a pretty decent rivalry somewhere in the mix. And, to be clear, there are some decent rivalries here. The Kings and Avalanche had an extremely dramatic two-year run in 2001 and 2002. Colorado and Dallas were already mentioned, but that was more of a firework than a full-blown fire. The two teams were never set up to harbor prolonged hate.
As for the rest? Well, Tampa Bay and Florida have still never met in the playoffs. Tampa Bay and Carolina met in the playoffs twice... but they did that seven years apart. Neither team has been particularly competitive on a regular basis. None of those teams have any legacy matchups in the other conference. That immediately eliminates three teams from our list.
Colorado hasn't managed to be relevant as most of these teams started winning on a regular basis. Their championship cycle coincided with those of the Stars and the Red Wings and the Devils. The Stars' run was even shorter-lived than the Avs'.
Arizona has refused relevance almost as a steadfast rule. I am sure that they consider teams like the Kings a rival, and the games usually have an edge to them, but there isn't a whole lot there.
St. Louis has somewhat close geographic ties to Nashville. They have a heated battle (along with Chicago) brewing for the best team in both the Central Division and the league as a whole. They do not, however, have even a single playoff matchup. There are certainly seeds (and a lot of fertilizer, particularly in St. Louis) here, but no water to make it all grow. Both teams would probably say that their most hated rivals are Chicago or Detroit, at least while the Wings were still in the west.
That leaves California.
The forced rivalry for the Kings is the Freeway Faceoff with the Ducks. Unfortunately, that title was the product of a rivalry naming contest. There is almost nothing organic about that rivalry on the ice. It exists because it is required to exist almost by law. It does not exist because it should. I've always figured that the Sharks and their fans view the Ducks much in the same way the Kings do: annoying baby brother.
The only teams left standing are the Kings and Sharks. Thankfully, you don't have to squint to see why this is the only rivalry in the western U.S. that NBC regularly highlights.
Almost two decades of friendly competition exploded over the past five seasons. Beginning in 2011, the Kings would face the Sharks three times in four postseasons.
The teams' interconnectedness twists all the way up from the players to the coaching staff to the front office. Head coach Darryl Sutter and general manager Dean Lombardi famously managed the Sharks together some time before joining the Kings.
Not many players on the current iteration of these two teams played for both. Only Christian Ehrhoff and Martin Jones fit this bill. However, the latter's case is particularly interesting. Jones is the third goalie the Kings have let go due to their long-term obligation to Jonathan Quick. While the first two (Jonathan Bernier and Ben Scrivens) retreated to irrelevance, the Kings will get to watch closely as Martin Jones flourishes or fails in the NHL.
Even with the emerging Martin Jones narrative, actual on-ice play dictates this rivalry more than anything else. There have been closely contested games. There have been dramatic comebacks, both in games themselves, and, uhm, otherwise. There has been physical play, there has been dirty play, and there has been some straight up weirdness. Hell, the two teams even had disappointing 2014-15 seasons to mirror each other. The games have become must-watch hockey for anyone willing to stay up that late.
Sunbelt teams often get maligned for their lack of fans or passion or whatever, but here we have two non-traditional markets with rabid fanbases and loads of success to go with it. It's important for the growth of the game for a rivalry like this one to exist. In an environment that is often dominated by the northeast, a couple of west coast teams have made themselves belong.