Alvarez, who turns 17 on June 19, was born in Los Angeles to Mexican parents. He played for the U.S. under-15 team in 2016, Mexico's under-15 team in 2017 and for Mexico's under-17 team last year. He has not played for the senior team for either nation.
"We want to create an environment that players want to be in," Berhalter said at a news conference Wednesday. "We want to create a playing style, a team spirit that players want to be a part of, and if we do we're confident that we can get players like that and we can keep players like that in our program."
Alvarez entered in the 68th minute Saturday and fed Daniel Steres for a header that tied the score in the 68th. The Galaxy went on to beat the Chicago Fire 2-1 in their opener behind an 80th-minute goal by Zlatan Ibrahimovic.
"It would be great that he continues to chip away and get playing time and now can be a consistent performer for one of the top clubs in MLS," Berhalter said. "And we'll be there watching the whole thing, and when he's doing what we expect him to do, there'll be an opportunity for him with the U.S. national team."
For his part, Alvarez told ESPN in September 2018 that "something happened during my last training session with the U.S. ... My parents got mad and everything, and when I came to Mexico they told me that if I wanted to go there, they would support me going forward. So I took the decision to come [to Mexico] to see if I liked it, and when I got back I told them that I wanted to stay."
Hired in December, Berhalter had an all-Major League Soccer roster when he coached the Americans' wins over young Panama and Costa Rica teams early this year. He will have Europe-based players available for the first time when the Americans play exhibitions against Ecuador at Orlando, Florida, on March 21, and Chile in Houston five days later.
He said top young American players who have established themselves with clubs, such as RB Leipzig midfielder Tyler Adams, will not play at the Under-20 World Cup in Poland, where the U.S. opens against Ukraine on May 24. At around the same time, the senior national team will gather for training ahead of its CONCACAF Gold Cup opener on June 18. Josh Sargent and Tim Weah also appear likely to be with the senior team.
"We looked at the U-20 roster and there's not that many overlapping players," Berhalter said. "There's some guys that just it's not realistic to expect that they're going to play in the U-20 World Cup given what stage they are in their development."
The Gold Cup will be the first competitive games for the U.S. since the October 2017 loss at Trinidad and Tobago that ended the Americans' streak of seven straight World Cup appearances. Berhalter said players reporting after European club seasons will be given a bit of a rest ahead of the Gold Cup.
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