ISTANBUL (AP) — It was not the way the United States wanted to start the Under-20 World Cup.

After a strong qualifying campaign and a victory over Portugal in a warm-up, the Americans were comfortably beaten 4-1 by tournament favorite Spain on Friday in Istanbul.

The result called into question the American strategy of pressing in attack for much of the match, which was largely at fault for several of the goals scored on counterattacks by the European Under-19 champions.

One day later, the U.S. players insisted they remain confident of advancing to the knockout stages and beating another well-fancied team, France, on Monday. They acknowledged making mistakes but said that would not change their strategy of being aggressive against France, which beat Ghana 3-1.

"We're still pumped, you know," said Benji Joya, who plays for Mexican club Santos Laguna. "We can't give up and we aren't going to give up."

Playing in one of the toughest groups, the Americans need a win to improve their chances of reaching the knockout stage in the 24-team tournament for the ninth time.

Coach Tab Ramos and his players understand the difficult task of beating a French team that has an explosive offense and features attackers Yaya Sanogo, Geoffrey Kondogbia — both of whom scored against Ghana — and captain Paul Pogba who plays for Juventus.

"It's certainly a challenge for us to get our team prepared for Monday," Ramos said. "I think we have a lot of positives to focus on. There are not many times when you'll find a team losing 3-0 that makes the type of effort that we made (against Spain)."

Midfielder Wil Trapp said beating France will be a "huge challenge" but one he relished.

"I think we would be rather be playing the best teams," Trapp said. "This way we are battled tested when we move into the next round."

Trapp also dismissed concerns about the team's defense which was repeatedly exposed by Spain's quick counterattack.

"It's a game of mistakes and unfortunately we made mistakes that were costly for us," Trapp said. "Pressing Spain the way we did is never an easy task just because they are such a technical and forward attacking team."

The defense has been a work in progress for the Americans, with midfielders Caleb Stanko and Shane O'Neill operating as converted defenders, along with the loss of Eric Miller to injury. The team was without O'Neill against Spain because he was serving a one-game suspension for a red card in the CONCACAF Under-20 championship.

Ramos, a former 15-year-old player at the Under-20 World Cup, defended the decision to press Spain.

"You come out and you play Spain and you try to play the game on their side of the field. It's a gamble," he said. "But with the way I see football, it's a gamble that I wanted to take."