Jurgen Klinsmann's men stumbled in Kingston, and their margin of error has now shrunk dramatically.
Friday's defeat to Jamaica in Kingston put Klinsmann's U.S. team in an uncomfortable spot in the semifinal round of World Cup qualifying in the CONCACAF region, a stretch of the road to Brazil in 2014 that it was expected to cruise through with little more than a smug wave to weaker opposition.
Instead, Jamaica's 2-1 victory means that the previously unthinkable scenario of the USA missing out on the World Cup is, while still unlikely, no longer beyond the realm of possibility.
Clint Dempsey's goal after only 36 seconds was the fastest in men's national team history and looked set to send the team marching further along the positive path of road results that included exhibition successes at highly-rated Italy and Mexico this year.
However, a spirited revival from a Jamaican team that is looking to clinch a place in soccer's biggest show for the first time since 1998 secured a comeback win for the Caribbean nation, thanks to free-kick goals from Rodolfo Austin and Luton Shelton.
It all means Klinsmann's men urgently need to beat Jamaica when the teams meet again in Columbus, Ohio, on Tuesday night. With three rounds of six now played, Jamaica leads the group on seven points, with the USA and Guatemala tied on four. Antigua and Barbuda sits in fourth place with one point.
The top two teams in the pool go through to CONCACAF's final qualifying stage next year, where three out of the six competing teams will automatically secure a place in Brazil.
American spirits were mightily high after the flurry of friendly performances that seemed to prove Klinsmann had the team heading in the right direction after some disappointing setbacks in the early matches of his reign.
But exhibition results count for nothing in reality and the events of Friday will be a blow to the confidence to a squad that was missing Landon Donovan and Michael Bradley but should have still had enough guile to survive this test with at least a share of the spools.
Defeat in what became a rugged and physical battle raised the worrying thought that this is a side that doesn't particularly relish a scrap, an accusation that could never legitimately be leveled at former head coach Bob Bradley.
For sure, Klinsmann's creation has a little more imagination about it, but not to the extent that many expected. He used four central midfielders here, had no real wide options and put out a lineup that didn't show a whole lot of enterprise. Jamaica, tough and hungry and with everything to play for, showed greater will and strength of character.
Jamaica "was hungrier," Klinsmann admitted. "They deserved to win."
Chances are, the USA will rebound strongly on Tuesday and then complete qualification to the next phase in the final two fixtures. If so, this will go down as a scare that served as a wake-up call, but it is one the side could have done without.
There is no margin for error now, and any thoughts of experimentation are gone as the plain task of reaching the next round is the only thing that can occupy the Americans' thoughts.
A one-off setback like this need not be greeted as a disaster, but its statistical repercussions pose a problem, one that must be dealt with with urgency.
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