The match went on to extra-time and Portugal's Adrien Silva gave them the victor in the 104th minute.
Adrien Silva converted the kick to give the European champions a hard-fought victory.
Portugal and Mexico drew 2-2 in the opening game of the group stage, when Hector Moreno salvaged a last-gasp point for the Gold Cup victor, but were left fighting for a consolation prize in the Russian capital.
Mexico goalkeeper Guillermo Ochoa appeared to be on his way to a man of the match award, saving a penalty from Andre Silva and making a series of key stops that preserved the lead.
Xbox One X will not generate profits for Microsoft
It's a little bit easier when you have a fixed spec, when you think about Xbox, Xbox One S, and Xbox One X. He was also asked about the UI for Xbox One X and whether it will be the same as the standard Xbox One.
Mexicans in the semi-finals lost the German national team 1: 4, interrupting their series of 7 unbeaten games.
Hernandez drove to the byline to the left of the area and drilled the ball back across goal and, when Patricio failed to intercept, the ball cannoned off Neto's shin and into the net. Portugal went in pursuit of an equaliser and Gelson Martins - replacing Ronaldo in attack - was denied by an excellent save from Ochoa with just over an hour played.
Manchester United and Barcelona target Nelson Semedo was given his marching orders immediately after the interval.