Atlanta United was warned by Club America manager Miguel Herrera that his team was among the most powerful in the Americas, implying that they weren’t going to hold back in Wednesday’s Champions League quarterfinal at Estadio Azteca.

Three goals in the first half were enough for Club America to beat Atlanta United 3-0 in the first leg of the series. The second leg is scheduled to be played on March 18 at Kennesaw State. Atlanta United must score at least three goals, and shut out Club America, to have a chance to advance to the semifinals.

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“If we score one (in the game) we have some hope, but 3-0 is very difficult,” Atlanta United manager Frank de Boer said.

Atlanta United knew the game would be difficult. In addition to Club America being one of the best teams in the Western Hemisphere, Estadio Azteca is at more than 7,000-feet altitude, Atlanta United was missing several key players because of injuries, lost another during the game, and the Mexican club was further motivated by losing to Atlanta United in last year’s Campeones Cup at Mercedes-Benz Stadium.

De Boer selected Brad Guzan in goal with Anton Walkes, Fernando Meza and Jeff Larentowicz as the centerbacks. Brooks Lennon started as the right wingback with Jake Mulraney on the left. Eric Remedi and Mo Adams were paired as defensive midfielders with Emerson Hyndman playing as an attacking midfielder. Ezequiel Barco and Pity Martinez were the strikers. The lineup was filled with interesting choices: Larentowicz had yet to start this season and has played centerback for just a few minutes this season. De Boer said he knows that Larentowicz played centerback when the team won the MLS Cup. De Boer said giving 18-year-old George Campbell his first start wouldn’t have been fair. Adams had yet to start, but de Boer said he wanted another midfielder. Pity Martinez and Barco had yet to be paired together as strikers this season. De Boer said they did well when paired together as strikers last year during a U.S. Open Cup game.

The lack of chemistry and familiarity was evident in the first few minutes.

Club America grabbed a 1-0 lead in the 11th minute on a rocket from 30 yards by Leo Suarez. The shot dipped into upper right corner. Suarez had time in the space in the middle of the pitch because Atlanta United defenders couldn’t get out quickly enough to close him down after an initial corner kick was cleared. Two players came close to blocking the shot, but the ball flew past them.

America increased its lead to 2-0 two minutes later when Henry Martin got past Meza, ran onto a pass from Richard Sanchez, who was closed down by neither Remedi nor Adams, and hit a left-footed shot into the lower right corner.

The lead grew to 3-0 in the 36th minute when Bruno Valdez headed in a corner from 12 yards. Valdez got away from Hyndman on what looked like a pick play run by America.

“We chose a tactical concept, not the normal way we play,” de Boer said. “More reserved, dropping a little bit deeper. The trip, the altitude, we decided to play really compact.

“We never really get the pressure on them. That’s on me. I made the decision.”

De Boer subbed on Matheus Rossetto for Remedi to start the second half and switched the formation to a 4-3-3 and decided to press Club America across the field. De Boer said that tactic couldn’t be done for 90 minutes because of the thin air and the fact that the team just played four days ago.

The performance in the final 45 minutes was much better, but the circumstances may have helped.

Rossetto played for 10 minutes before he needed to be subbed off with an ankle injury, according to de Boer. Manuel Castro came on in his first appearance.

Looking for the important away goal that could make next week’s return leg more interesting, de Boer subbed on Adam Jahn for Mulraney in the 66th minute.

Atlanta United pressed for the goal. Jahn was taken down in the penalty box but nothing was given by the referee. A few minutes later, Pity Martinez hit the crossbar and then the post with a free kick and hit the crossbar again with another shot in stoppage time.

“I’m really proud of the guys the way they played the second half,” de Boer said. “We really deserved a goal. But we lost the game in the first half.”

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