COUVA, Trinidad -- By one measure, the end came all at once. Three results across CONCACAF, all of them bad for the United States men's national team, left the Americans in fifth place of the Hexagonal and out of the World Cup for the first time since 1986.
But by another, the disaster for the U.S. program was built slowly but steadily, borne out of the same repeated mistakes and systemic failures that occurred throughout the qualification process. The squad formed by Jurgen Klinsmann and shaped further by Bruce Arena dodged their way out of catastrophe after catastrophe until the moves ran out just before the finish line. Although the inability to qualify for Russia wasn't inevitable, it's easy to look back at the qualifying cycle and note the shortcomings that had lasting repercussions.
Here are the five things that went wrong in this qualifying campaign.
1. The U.S. never found a center-back pairing
The Americans began the final round of qualification with a back three of Omar Gonzalez, John Brooks and Matt Besler in a home match against Mexico. Uncomfortable and out of rhythm, that trio lasted less than a half before Klinsmann switched to a back four at the behest of his players. In the next nine games, the U.S. tried six more combinations: Gonzalez-Brooks, Gonzalez-Tim Ream, Cameron-Brooks, Gonzalez-Cameron, Cameron-Ream and Gonzalez-Besler.
This constant shuffle came out of necessity -- both Brooks and Cameron missed significant time with injury -- but also there was the nagging fact that each of the pairings showed faults. Gonzalez and Besler played the final three matches together, and it was Gonzalez's failure to clear a cross that resulted in Trinidad and Tobago's opening goal on Tuesday night.
"One of the most unlucky goals ever, I think for myself and ..." the emotionally devastated center-back said before trailing off. He took a second to think, then continued. "It's one that will haunt me forever."
2. The U.S. never found a partner for Michael Bradley in center midfield
The American captain played with Jermaine Jones, Christian Pulisic, Darlington Nagbe, Kellyn Acosta and by himself in the center of the field. There were flashes of excellence (the Bradley-Acosta duo was spectacular in Mexico) but nothing that worked over a long period of time.
There were myriad problems: The Toronto FC midfielder needed to cover too much ground, was constrained by his partner or didn't know where to go because his counterpart was freelancing all over the field. The spine of the team wasn't strong enough throughout qualification, and it started in the middle. While Bradley is 30 and jettisoning him now would be a mistake, the future is coming soon.
3. The U.S. couldn't find a consistent way to goal
On Tuesday evening, the Soca Warriors routinely put nine and even 10 players behind the ball, conceding space and possession to the visitors. That did not, however, materialize into many chances. On the night, the Americans couldn't muster much of an attack, which was something of a theme during the campaign.
"They sat aback, which we've had trouble with in the past. We weren't good enough to break them down," Tim Howard said following the match. "We were second to a lot of balls. [We] didn't hold onto enough balls."
During the Hex, the U.S. scored 10 goals in combined home routs over Honduras and Panama; they tallied just seven scores in the remaining eight games. That's a lot of failure against bunkered defenses. The Americans simply weren't sharp enough, too often making poor first touches or passes that were slightly off. Throughout the cycle, they were neither precise enough nor technical enough.
After more than two years of watching the same story play out, it's fair to wonder how much comes down to nerves and situation, a frequent American talking point, and how much is a result of the squad simply not being quite good enough.
4. The U.S. didn't get A+ play from its goalkeepers
This is an absurd request, but it's also something upon which the Americans have come to rely. How many times have Brad Friedel, Kasey Keller, Tony Meola, Tim Howard, Brad Guzan and the like bailed out a porous U.S. backline over the years? Far, far too many to count. A world-class goalkeeper shouldn't be a solution; it should be a last resort. Neither Howard nor Guzan approached the required level during the Hexagonal.
The Colorado Rapids shot-stopper showed his age at 38 and hasn't regained his elite athleticism following surgery last year. Guzan is serviceable and occasionally brilliant but never commanding and lacks the presence of his elder counterpart. Nick Rimando, the third-stringer the last two games, is 38 as well. That's 109 years of goalkeeper: too many notches in the gloves.
5. The U.S. failed to win at home
The road to qualification in CONCACAF is simple: Earn draws on the road, and take three points at home. The Americans lost four Hex games for the first time ever and failed to do either, but it was the home defeats that sunk the campaign. The U.S. lost to Mexico to begin the final round, a capitulation that got everything off on the wrong foot.
"Quite frankly, after November 2016, we had an eight-game Hex, and we had to play flawlessly," Howard said. "That's one hell of an uphill battle for anybody. We left ourselves no room for error, and we paid for it."
The amazing thing is that even this isn't true. Despite losing their first two qualifiers, the Americans had plenty of wiggle room. They still did after failing to find a goal in a winnable game against Costa Rica at Red Bull Arena. Heading into the final match, the red, white and blue needed a draw against the worst squad in the six-team tournament, a group that had lost eight of its previous nine qualifiers. Arena's crew couldn't even manage that, and they'll be watching the 2018 World Cup from the couch at home.
What a debacle.
Noah Davis is a Brooklyn-based correspondent for ESPN FC and deputy editor at American Soccer Now. Twitter: @Noahedavis.