The 22-year-old played for Mexico at the under-20 and under-23 levels but did not make an appearance for the senior team, according to ESPN. Per FIFA's rules, Gonzalez was eligible to change his association as a dual national since he didn't make an appearance for the senior team at an official competition.
Gonzalez wasn't listed on the final roster for the Gold Cup, though he is eligible to play for the team after the group stages if called upon.
The young goalkeeper might prefer to remain with FC Dallas this summer, however. ESPN reported "a source recently told ESPN FC that Gonzalez had expressed uncertainty about leaving FC Dallas at the moment, as international duty could jeopardize his spot as the MLS team's starting goalkeeper."
He's been excellent for FC Dallas this season, accumulating five clean sheets in 13 starts.
The United States and Mexico were both vying for Gonzalez's services, with ESPN noting that "Mexico national team manager Juan Carlos Osorio had recently spoken to Gonzalez about his future, and that he had hoped to call up Gonzalez in the future."
Gonzalez now will be in the mix to be one of the future potential starters for the USMNT, as many of the program's mainstays at the position are nearing the end of their careers.
As Bruce Arena told Grant Wahl of SI.com earlier in June: "I'm looking down the road for U.S. Soccer, and they're going to need to have some young goalkeepers emerging."