As the MLS Cup playoff chase continues to heat up, the most important game on the San Jose Earthquakes calendar is at hand. No, we're not talking about the Quakes visit to Chivas USA this Sunday, though it is critical they get a result at the StubHub Center. Rather, the match that is a must-win for San Jose doesn't even involve the Earthquakes. In fact, it will be contested nearly 3000 miles away, by teams that do not even call the United States home.

The most important game of the year to date for the Earthquakes is the CONCACAF Champions League group five match between the Montreal Impact and CD Heredia of Guatemala at Stade Saputo on Tuesday.

San Jose's CCL future is not in its hands, despite the comprehensive 3-0 shellacking they put on the visiting Impact last week at Buck Shaw Stadium. The victory was important, as it created separation between the Quakes and the Impact in the Group 5 standings, but Heredia still sits atop the group needing only a point against Montreal to advance to next spring's knockout round of the tournament. For at least one day, every Earthquakes supporter will also be an Impact supporter. The Bleu-et-Noir from Quebec need all the help they can get from the Blue-and-Black from San Jose.

For that matter, every fan of MLS should also be cheering on the Impact against Heredia. By virtue of the CCL draw, Group 5 was assigned two representatives from MLS -- the Supporters' Shield winning Earthquakes and the Canadian champion Impact. The "Group of Death" moniker was coined by some in the media to highlight the expectation that the two MLS sides would likely battle each other for group supremacy. At the time the draw was made, the third team in the group was simply referred to as "Guatemala side #2" -- no doubt a pushover entrant from the tiny Central American nation.

Instead, little-respected Heredia, assigned both those same scribes to bolster each side's points total, flipped the script and posted duel 1-0 victories over the visiting Quakes and Impact and venture north to Montreal with control of their advancement fate.

The Earthquakes will get their crack at the Guatemalans on October 23, but for that game to matter, Montreal needs to win. In some ways, the Quakes big win against the Impact last week nearly killed off the Canadian sides hopes of advancing, as goal differential is the first tie-breaker to determine the group winner in the case all 3 teams finish tied on 6 points -- the outcome San Jose needs to prolong its own stay in the tournament. For Montreal to have a chance of advancing, they need to beat Heredia by at least 5 goals.

With its own pursuit of an MLS Cup playoff berth reaching a boiling point, the Impact have suggested that its commitment to its CCL is well on the wane. But this is shortsighted -- not only by Montreal, but also by MLS as a whole. A Heredia tie or win on Tuesday knocks out the Impact as well as San Jose -- a potential twofer that should have all MLS fans anxious at the potential outcome. Given the league's stated goal to improve its standing on the international stage, getting as many of its representatives into the next round of the CCL is paramount to anything else.

Not just for the Impact, not just for the Earthquakes, all MLS fans should demand the best out of Montreal against Heredia. As was the rallying call across the country two years ago when Real Salt Lake was inching ever so close to winning the tournament and representing the region in the FIFA Club World Cup and soccer fans flooded social media with messages of support for RSL, those same fans need to do the same for the Impact on Tuesday.

On Twitter in 2011, the hashtag was #MLS4RSL -- this week's update should be #MLS4Montreal. Real Salt Lake players were inundated with messages of support as they advanced to the CCL final round against Mexico side Monterrey, and even when they fell one goal short, were still celebrated for almost achieving the pinnacle of CONCACAF club soccer, the appreciation was still forthcoming. Two year later, the desire of MLS fans to see their league succeed has never been greater; it is now or never to show that pride.

The Impact kick things off on Tuesday at 5:00 p.m. (SPORTSNET, TVA Sports, Univision Deportes Network) from Stade Saputo. Nothing less than a packed house is required to push the Impact to victory. And for the rest of MLS fans, in San Jose and beyond, the push comes with support in any way possible. For one day, we are all Impact fans. For one day, we are #MLS4Montreal.