This Heineken Rivalry Week – already in full swing since Wednesday's 3-3 Texas Derby – will feature plenty of the usual flashy fireworks and hyped up banter. But at least one of these match-ups is going a little undersung, if you will.

The Rocky Mountain Cup returns this Saturday (10 pm ET; MLS LIVE), with Real Salt Lake set to host the Colorado Rapids at Rio Tinto Stadium. The long-running matchup between RSL and Colorado might not have the bold names of some of this weekend’s other contests. But what lacks in star power it more than makes up in bitter, bitter salt and, for MLS nerds, some bellwethers of where these two teams might be going.

If you’re outside of Salt Lake City and Denver or if you're newer to the league, it’s easy to forget some of the fireworks that happened on the field and on the sidelines between these two teams just before social media really exploded.

The rivalry dates back to when RSL entered the league in 2005, and some of the golden years of the matchup happened just a few years after that. Like, oh, that time in 2006 when Pablo Mastroeni – then just a player for the Colorado Rapids – stuffed his shirt down his pants in anger at then-RSL owner Dave Checketts and gestured rudely at RSL fans.

Then there was that other weird time they played to a 1-1 draw in May 2007 – a match in which both sides managed an own goal each.

Some of that institutional memory lives on through longtime team stalwarts, like Kyle Beckerman. His trade to RSL from the Rapids – way back in 2007 – helped foment some of the rancor that lives on today. (Here’s Jeff Carlile writing on that – and Beckerman’s then-questionable prospects, funny by the light of 2017 — for ESPN back then.)

But potentially what’s more interesting about Sunday’s matchup is what it says about these teams in 2017. Mastroeni, mentioned above, of course departed as head coach of the Rapids last week. And after an impressive record in 2016, this year has proved pretty bleak for the ’Pids. With the team sitting in 10th in the Western Conference standings, it’s pretty much too late to hope for a turnaround for this year.

Still, Saturday's match could hint at where the near future lies for Colorado. Their defensive soccer didn’t cut it this year, and their strategy needs to change dramatically. We saw glimpses of it in interim head coach Steve Cooke's debut last week -- might we see more against Real Salt Lake?

The latter, meanwhile, look poised for a very late-season turnaround. Under Mike Petke – he of the famous recent postgame rant that launched a thousand memes – both team and fans seem reinvigorated. They just trounced the San Jose Earthquakes 4-0 at the RioT, and the Quakes have been pretty solid this season. The RSL of a few months ago would not have managed that.

Like my colleague Charles Boehm said here, at their best, they’re looking like classic Real Salt Lake, and an RSL win could whip up some serious reverberations in the middle of the Western table. Of course, you’ll have to follow the action of the Rocky Mountain Cup to find out if and how that turns out.