LOS ANGELES — For Jurgen Klinsmann, the Copa America Centenario was something of a finishing school for his U.S. men's soccer team, a place for his players to grow in skill and confidence while learning they can compete with the best teams in the world.

“The more they have the opportunity to play these teams, the more confident and comfortable they will become,” said Klinsmann, whose team made a surprise run to the semifinals before getting shut out by Argentina and Colombia to finish fourth in the 16-team field.

“They see that there's nothing so different. That we're growing, that we're getting stronger.”

But the tournament was also an education for Klinsmann and his coaching staff, who must now apply the lessons of the past 23 days to their preparation for a World Cup qualifying tournament that resumes in September.

“You saw so many good pieces, so many things that make us optimistic looking forward,” Klinsmann said. “Every day you learn. You learn about every individual, about your group, about the chemistry. So many little pieces.

“Every day was a learning day. And there are many more to come.”

Just as there were many takeaways that will guide the staff toward the 2018 World Cup in Russia:

The pairing of Geoff Cameron and John Brooks in central defense was, at times, brilliant and may have solved one of the most vexing problems Klinsmann has had to deal with in his five years as coach.

Bobby Wood, who played as a hold-up striker, had a breakout tournament clearing space for Clint Dempsey. Fast and aggressive, he gives Klinsmann a dangerous option for the oft-injured Jozy Altidore.

Teenager Christian Pulisic didn't play much — just 85 minutes off the bench — but he showed poise and game-changing talent when he was on the field.

The midfield remains a mess. Bad days appear to be more frequent than good ones for Michael Bradley. And though Jermaine Jones played with ferocity, his absence against Argentina once again proved the U.S. has no one to replace him — a problem since Jones, at 34, is the second-oldest player on the team, behind goalkeeper Tim Howard.

Brooks, who led Copa America in clearances before sitting out Saturday's third-place game with a knee injury, was the revelation of the tournament for the U.S. He and center-back partner Cameron were solid in front of goalkeeper Brad Guzan, helping the U.S. go 302 consecutive minutes without surrendering a goal.

Outside backs Fabian Johnson and DeAndre Yedlin — who, like Cameron and Brooks, play for top clubs in Europe — were also spectacular at times, turning what had been a weakness into strength.

“We're building a back line toward Russia that is very talented. And these players, they're used to playing the big players in Europe,” Klinsmann said.

Wood and Pulisic are also building toward Russia, albeit at different speeds. Klinsmann brought Wood along slowly, starting him just three times last year. That produced a hunger that fueled Wood this year.

Now Klinsmann is following the same go-slow approach with the 17-year-old Pulisic.

“You don't want to burn a Christian Pulisic right now against these top teams,” he said. “You want him to get a taste. He will eventually get better over time. So this is a natural path.”

But Pulisic alone won't solve the problems of a midfield that has tactical and technical deficiencies. The U.S. was dominated in possession and passing accuracy, and much of the blame rests with a midfield that had its pocket picked repeatedly.