Oct. 10, 2017, is a day that still sends shudders through the U.S. soccer ecosystem. It was on that day that the U.S. men's national team lost 2-1 to Trinidad and Tobago and, combined with an otherworldly confluence of events, the result saw the U.S. eliminated from qualification for the 2018 World Cup.

The aftereffects were seismic. Bruce Arena resigned as U.S. manager a few days later. U.S. Soccer Federation president Sunil Gulati ultimately decided not to seek reelection. The result also ushered in a new generation of players, a group that ultimately qualified for the 2022 edition of the World Cup in Qatar, with the U.S. reaching the round of 16.

But wounds, emotional and otherwise, leave a scar. Scars may heal, but they never completely go away, either. There is a sensitivity to what transpired, and discomfort at the memory.

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For some, those recollections will be at the forefront Monday, when the U.S. faces T&T in the second leg of its Concacaf Nations League quarterfinal. While the match will mark the fifth time the two teams have squared off since that fateful night at the Ato Boldon Stadium in Couva, Trinidad -- including Thursday's 3-0 win in the first leg -- it will be the first time that the U.S. will have played in T&T. This time, the match will be held at the Hasely Crawford Stadium in Port of Spain. If the U.S. takes care of business, not only will progress to the CNL semis be assured, but so will qualification for next summer's Copa America, a vital tournament in terms of preparation for the 2026 World Cup.

It doesn't take much for the memories to come flooding back. Parts of the pitch was literally underwater the day before the match, rendering the U.S. training session a nonstarter. There was the early missed chance by Jozy Altidore, the calamitous own goal from U.S. defender Omar González, and then the absolute dart unleashed by Alvin Jones that put T&T 2-0 up.

Christian Pulisic's goal two minutes into the second half provided some hope, but as the minutes ticked by, the tension began to rise and became unbearable. Clint Dempsey hit the post in the 77th minute. The results elsewhere in Concacaf began to tilt against the U.S., including a phantom goal by Panama striker Gabriel Torres that never crossed the line and set the stage for Roman Torres' late winner. Honduras' win over Mexico sealed the Americans' fate, and they were left to trudge off the field having suffered the biggest embarrassment in the program's history -- even eclipsing the 40-year period from 1950 to 1990, when failing to qualify was the rule and not the exception.

Current U.S. midfielder Weston McKennie, then breaking through with Bundesliga side Schalke 04, recalls waking up in Germany at the house of then-club teammate Nick Taitague, only to be stunned at result.

"We woke up in the morning and just was like, 'Oh my God, we didn't qualify for the World Cup,'" McKennie said prior to Thursday's match. "We watched the goals and there were crazy goals. So that goes to show soccer can be any team's game on that day. And that what was shown during that game as well."

With Pulisic currently injured and not with the U.S. at the moment, defender Tim Ream is the lone holdover from that squad that made the trip to Couva. He's been a professional for more than 13 years, and thus has had to process many moments, both highs and lows.

So which moments stick with a player the most: the highs or the lows?

"I think you remember both, because they're both ... learning experiences," Ream said following Thursday's match. "But for me I tend to focus on the highs and the positives because I think over the course of a career there's so many moments, and when you dwell on negatives, they just kind of pile up and keep coming. So I tend to remember the better moments more than the bad moments. But that doesn't mean that they're not there in the memory bank."

Will they be there Monday?

"No, absolutely not. I moved past that long ago," he said. "For me, obviously I'm the only one here that was a part of that, but to be completely honest, that's been put so far out of mind that I'm not even thinking about it."

The topic of that U.S. humiliation has come up at times during this camp for the better to make sure that the USMNT plays with the requisite intensity.

"I could kind of feel the spark, and kind of feel the fuel of the team, of the staff and how special this game is; the history behind it and what it did to U.S. soccer on that day," winger Kevin Paredes said.

The emphasis hasn't all been negative in the current camp, with the U.S. trying to put the focus on another famous incident that took place in Trinidad. That would be Paul Caligiuri's "Shot Heard 'Round the World," the goal that in 1989 beat T&T 1-0 on the final day of qualifying for the 1990 World Cup. The win put the U.S. in the World Cup for the first time in 40 years and provided a massive jolt to the U.S. men's program.

U.S. manager Gregg Berhalter brought Caligiuri in to speak to the team ahead of Thursday's match. The former U.S. international brings a perspective of not only scoring to put the U.S. in the World Cup, but also as one of the early pioneers of U.S. players heading overseas, having signed with then-German powerhouse HSV Hamburg in 1987.

"At some point in my life, I wanted to prove to the world that Americans could play soccer," he told reporters prior to Thursday's match. "We're past that stage. I mean, we're obviously respected. I think America loves soccer. America loves our men's national team, our women's national team, and the ones that don't love us, fear us, and that's a whole different level of the game that we're at today."

Caligiuri now marvels at how much the sport has evolved in the years since he retired. He feels this is the best U.S. men's team ever, and there isn't a single area of the sport that hasn't grown immensely. But his goal remains a massive turning point for the sport in this country.

"I think it does resonate with a lot of people, and it was an important moment, not just for soccer in terms of the men's national team. I think it's global soccer," Caligiuri said. "It's really brought soccer to the forefront in this country, enabled us to host World Cups, both the men's and women's, and it exposed this great sport to the rest of the country."

Thanks to three goals in the last eight minutes of Thursday's match, there doesn't figure to be much drama in Port of Spain on Monday. But that isn't to say the U.S. is taking anything for granted.

"We're in a good position, but crazy things happen," Berhalter said after Thursday's match.

That night in Couva six years ago is a not-so-subtle reminder.

Arch Bell contributed reporting for this story.