Al Moez Ali scored twice as Qatar became the first team to reach the semi-finals at the Gold Cup holding on to beat El Salvador 3-2.
Abdelaziz Hatim also scored for the reigning Asian champions in the quarter-final clash in Arizona.
Joaquin Rivas had both goals for El Salvador, who mounted a comeback in the second half.
Ali opened the scoring in the second minute by capitalizing on an El Salvador giveaway. Just six minutes later, Hatim hammered a right-footed shot into the goal to make it 2-0.
El Salvador were called for a handball in the 55th minute, which resulted in Ali scoring his second of the game off a spot kick to give Qatar a commanding three-goal lead.
But El Salvador were not about to go quietly as their comeback started in the 63rd minute when Amando Moreno made a touch pass to Rivas, who scored to cut the lead to 3-1.
Rivas scored again 11 minutes later with a left-footed blast after taking a pass from teammate Bryan Tamacas.
El Salvador pressed for the equalizer in the final minutes but that was as close as they would get.
Holders Mexico cruised past a depleted Honduras squad that had lost several players to injury and Covid-19 safety protocols.
Striker Rogelio Funes Mori scored a header in the 26th minute to open the scoring for Mexico, who will next face either Canada or Costa Rica.
Jonathan Dos Santos and Orbelin Pineda then scored seven minutes apart to break the game open at the State Farm Stadium in Phoenix, Arizona. Dos Santos took advantage of a Honduras defensive mistake to volley a shot from the semi-circle into the back of the net in the 31st minute.
Pineda took a cross from teammate Jesus Corona and headed it in to give the Mexicans a sizeable lead at the half and they cruised from there.
In the other game,