Alvarez, the Galaxy phenom who is eligible for both countries, set up Mexico's first-half equalizer with a deft chip that was headed in by Santiago Muñoz.
Alvarez exited the game at halftime, and the teams stayed in a stalemate through 90 minutes, forcing extra time. In the extra period, Mexico pulled ahead through Israel Luna's tap-in off a low cross.
While Mexico retain the U-17 regional title, both countries – as well as semifinalists Canada and Haiti – qualify for the 2019 U-17 World Cup, which will take place in Brazil later this year.
- 9' – USA – Griffin Yow
- 17' – MEX – Santiago Muñoz
- 108' – MEX – Luna
USA: GK: Damian Las (Chicago Fire); Joe Scally (NYCFC), Adam Armour, Kobe Hernandez-Foster (LA Galaxy), Tayvon Gray (NYCFC); Danny Leyva (Seattle Sounders), Gianluca Busio (Sporting KC), Adam Saldana (LA Galaxy), Griffin Yow (D.C. United); Gio Reyna, Alfonso Ocampo-Chavez (Seattle Sounders)
- 70' – Ricardo Pepi (FC Dallas) for Griffin Yow
- 86' – Tyler Freeman (Sporting KC) for Alfonso Ocampo-Chavez
- 106' – John Tolkin (New York Red Bulls) for Adam Armour
- 116' – Gilbert Fuentes (San Jose Earthquakes) for Adam Saldana
Mexico: GK: Eduardo Garcia; Jose Ruiz, Victor Guzman, Rafael Martinez, Emilio Lara; Eugenio Pizzuto, Bryan Gonzalez, Kevin Mariscal, Efrain Alvarez (LA Galaxy), Israel Luna, Santiago Muñoz
- 46' – Luis Martinez for Efrain Alvarez
- 51' – Josue Martinez for Eugenio Pizzuto
- 81' – Leonardo Correa for Santiago Muñoz
- 109' – Kevin Ortega for Kevin Mariscal