Although Brenden Aaronson has been in Austria for only half a year, he has had years’ worth of development in his game.

To watch the 20-year-old Medford native play for Red Bull Salzburg this spring was to watch him grow up in real time, adding quality and sharpness levels beyond what he showed with the Union.

“In MLS, a lot of teams will sit back a little bit, but in the Austrian league you have teams that even though you’re the top team in the league, you have guys that are flying at you [in] no time,” Aaronson said. “I think the time that I’ve been here, my decision-making in the final third has just gotten quicker and faster … and I think it’s coming off really well, too.”

It sure has. Aaronson registered seven goals and five assists in 25 games for Salzburg, and many of those plays were of real quality.

He helped Salzburg win the Austrian league and domestic cups, and earned some shiny decorations for his new home. It also means he’s won three trophies across two countries in seven months, starting with the Supporters’ Shield with the Union. That kind of run is a rare feat for any American player.

“It’s been a whirlwind of six months for me, and it’s been a crazy time,” Aaronson said. “It’s not always easy to come over and get acclimated right away and get into the group — you’re meeting new friends and coming into a new system and all these kinds of things, and it was tough at first. … I think it was having the confidence of my teammates and my coaches, and that’s what kind of helped me push on.”

Now Aaronson is set to take his talents to a new level with the U.S. national team. He’s one of 23 players on the best-of-the-best squad that will play in next week’s Concacaf Nations League final four in Denver, and before then visit Switzerland in a friendly on Sunday (2 p.m., ESPN, UniMás and TUDN).

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A historic season for Americans

Also on the squad is Aaronson’s former Union teammate Mark McKenzie, who helped Belgium’s Genk win the Belgian Cup and finish second in the league — earning a berth in next season’s Champions League qualifying playoffs.

So are Downingtown’s Zack Steffen, who with Manchester City this season became the first American man to ever win the English Premier League; and Hershey’s Christian Pulisic, the star of stars, who will likely play for Chelsea against Man City in Saturday’s UEFA Champions League final (3 p.m., CBS, Univision and TUDN).

Steffen will be on the bench as City’s backup goalkeeper, but it’s still historic that an American man will be on each side of the field in the biggest game in world club soccer. And it’s guaranteed that an American man will lift a European trophy for the 14th time this season. If Chelsea wins Saturday, Pulisic will become the 10th player on the Nations League squad to earn a winner’s medal in the campaign.

Aaronson called it “an unbelievable number.” Many people who’ve been watching American soccer since before he was born have said the same.

“You’re seeing where they’re playing at, and they’re winning big trophies and it’s huge — it’s a really big step in U.S. football,” he said, showing another sign of how long he’s been abroad. “I’m really excited for the group of guys, and now it’s just pushing onto the Nations League and winning a trophy with this group of guys.”

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The Switzerland game is more than just a warm-up contest. It’s a chance for the U.S. team’s Europe-based players to play together, and to play at altitude before heading to Denver. St. Gallen is near the Alps, and while the city’s elevation is around 2,300 feet, the U.S. team has been training in the mountains.

The quick travel time from Europe to America is also intentional: It replicates what the players will experience when they come home for World Cup qualifying games starting this fall. After the Nations League games — June 3 vs. Honduras, and June 6 vs. Mexico or Costa Rica — there will be another friendly, vs. Costa Rica in suburban Salt Lake City on June 9. Then the players will finally get a well-earned summer vacation.

“A lot of us haven’t done it,” Aaronson said of the packed itinerary. “It’s really tough — it’s hard on the body because you’re traveling, what, eight hours back to the United States over a flight and then you have to get another flight and then get ready for a game in three days. It’s one of the toughest parts about football and playing for your national team.”

But he would never turn it down. And he knows what the whole team knows: This is the first time the U.S. men’s program’s true A-team has been together in years. The fan base wants this team to make a statement and win a trophy.

“It’s always an honor, and I think that you’re going to do whatever you can to get on the field no matter what,” Aaronson said. “It’s a good kind of test, and I think we’re going to do well with it.”

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USMNT schedule

  • Sunday, May 30: Friendly vs. Switzerland at Kybunpark, St. Gallen, Switzerland, 2 p.m. (ESPN, UniMás, TUDN)

  • Thursday, June 3: Concacaf Nations League semifinal vs. Honduras at Empower Field at Mile High, Denver, 7:30 p.m. (CBS Sports Network, Paramount+, Univision, TUDN); Mexico vs. Costa Rica, 10 p.m. (Paramount+, Univision, TUDN)

  • Sunday, June 6: Concacaf Nations League final or third-place game at Empower Field at Mile High, Denver, 9 p.m. (final; CBS Sports Network, Paramount+, Univision, TUDN) or 6:30 p.m. (third-place game; Paramount+, UniMás, TUDN)

  • Wednesday, June 9: Friendly vs. Costa Rica at Rio Tinto Stadium, Sandy, Utah (ESPN2, UniMás, TUDN)