CHARLOTTE, N.C. -- Let the real tournament begin.

As much as the United States men's national team might not have wanted to disrespect their Gold Cup Group A partners, there was never any real concern from the team it would fail to advance to the knockout round. Sunday's thoroughly dominant 6-0 win against Trinidad and Tobago showed why.

For the U.S., the group stage was all about integrating players, building rapport and setting the team up to win its fourth-straight Concacaf trophy.

"I think right from the beginning the message is sure that we give as many players opportunities to experience this group stage," interim coach B.J. Callaghan said on Saturday. "We know with that experience it'll only pay dividends in the short term, but also when we get to the long term."

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Jesus Ferreira is the best example of that. In the short term, the striker's back-to-back hat tricks in the last two games were what allowed the U.S. to win the goal differential tiebreaker with Jamaica to top Group A. Those performances are a positive sign for the USMNT's improving long-term depth at the position.

During the last World Cup cycle, striker was a glaring problem for the U.S. No one grasped the starting role during qualifying, and it was the team's most obvious weakness at the tournament in Qatar.

Ferreira, of course, was part of that equation. It's not that he played his way onto the 26-man World Cup roster as much as other options played their way off. Even so, his inclusion was subject to great debate, and when he finally saw the field -- as a starter in the Round of 16 against the Netherlands -- the stage proved too big.

Given the circumstances, his performance wasn't surprising. Calling on a 21-year-old MLS striker to make his World Cup debut against one of the most talented back-lines at the tournament inadvertently set him up for failure. And with that came a lasting impression that can only come from the sport's biggest stage.

Since then, Ferreira has responded about as well as possible. He scored against Mexico in an April friendly to keep the team's now six-game unbeaten streak in the rivalry alive. He's third in MLS with 10 goals in 18 games. His six goals in three Gold Cup matches ties the record for the most goals by a player in the tournament by a player 23-or-younger (with possibly three matches still to play).

"I think all forwards are going to be judged by the goals that they score first and foremost," Callaghan said. "And when I see his movement and his confidence in the penalty box, you can tell that the game has slowed down for him and he's just placing balls into the back of that and that's a positive sign. It lets us all know that he's focused and committed to being a goal scorer for us."

There are the obvious caveats about levels of competition. His three career USMNT hat tricks, which ties Landon Donovan for the most in team history, have all come against overmatched Caribbean competition. That reality is important context, but it also doesn't mean scoring six goals in an 88-minute stretch isn't worth celebrating.

USMNT players in the past also had opportunities to score against the lightweights of Concacaf and few took those chances as well as Ferriera. He's the first to ever record back-to-back hat tricks. In 21 career games, he's scored 14 goals. He's also shown to be a selfless player. That trait was a large factor in why coach Gregg Berhalter brought him to Qatar. After his first-half hat trick put the game out of reach and it was clear the U.S. would hold on to the goal differential tiebreaker against Jamaica, Ferreira might have been the team's most active player trying to win possession back.

"I think it helps the team. It shows that we're still in it and it kind of gets everyone going again," Ferreira said of his defensive effort. "I know people are tired. I'm used to playing in the heat, so I have maybe a little bit more energy than the rest.

"I always want to be the guy that can bring energy to the team and can spread that energy. We always say that someone can be contagious with their energy and so for me it's always being that person that can get everyone going."

It didn't go unnoticed by Callaghan.

"All of the work that he's doing leading our line defensively, dropping down, helping build up play," Callaghan said. "For me, he's having a really complete tournament so far and we're going to continue to get him better."

It also doesn't mean he's going to unseat Folarin Balogun as the presumed starter with USA's full team any time soon. It doesn't mean he's a better option than Ricardo Pepi, his former FC Dallas teammate, as a pure striker. It is, however, encouraging for the continued improvement of the depth at the position.

There were memorable performances from other attacking players, too. Cade Cowell and Gianluca Busio scored their first senior national team goals as the U.S. kept the pressure on until the final minute. Cowell's goal, especially, showcased what he can do, using his speed to get free on goal before he navigated past the goalkeeper and lone defender in the box.

"He was running at defenders relentlessly," Callaghan said of Cowell. "He was able to go inside, he was able to go outside. He was able to create combination play and then he gets rewarded with the goal."

As the winner of Group A, the U.S. will play the runner-up from Group D in Cincinnati on July 9. That opponent will be determined on Tuesday, when Guadeloupe (four points) plays Guatemala (four points) and Canada plays (two points) and Cuba (zero points). Of those, only Cuba has been eliminated.

Alan Sonora, who strained his hamstring against St. Kitts and Nevis, will not continue with the team in the knockout stage, Callaghan said, but his roster replacement has not been determined. Jordan Morris was available off the bench on Sunday and will remain with the team, along with Miles Robinson who started and played the first half.

Midfielder Aidan Morris left the team for personal reasons, the team announced on Sunday, and it is unclear if he will return during the tournament.