Mexico expanded their record number of Concacaf Gold Cup wins as Jonathan dos Santos' strike gave them a thin triumph over the United States.
LA Galaxy midfielder Dos Santos hooked on to a brilliant Raul Jimenez back heel to fire in off the bar before 62,493 fans at Chicago's Soldier Field.
Christian Pulisic had a decent early shot yet US manager Gregg Berhalter said Mexico were the "better group".