LISBON — The majority of the players called in to the United States men’s national team’s training camp here this week were not in Trinidad and Tobago last month when the squad endured a humiliating end to its World Cup qualifying campaign.

A few of them weren’t even awake.

“I was in bed and woke up in the middle of the night to a bunch of texts,” said defender Matt Miazga, who plays his club soccer in the Netherlands. “I watched the highlights in the morning. It was shocking.”

In the wake of that defeat, U.S. Soccer this week left home the core of the team that failed to qualify for Russia and instead assembled an experimental roster — a mix of veterans, newcomers and even a few teenagers — for next week’s friendly against Portugal. But that change in personnel has done little to dissipate the thick cloud of trauma that followed the coaches and players onto the field on Wednesday as they took their first steps into a yearslong competitive purgatory.

The World Cup is seven months away, and the only game on the Americans’ schedule is Tuesday’s exhibition in Leiria. The coaching staff is temporary. The federation’s leadership is in disarray. There are more questions than answers.