Silvio Romero's second-half brace saw America come from behind to see off Jeonbuk Motors 2-1 and book a meeting with Real Madrid in the last four of the Club World Cup.
The Liga MX side, who qualified as winners of the CONCACAF Champions League, were knocked out at this stage of the competition last season, but Sunday's win in Suita earned them a glamour tie with the European champions on Thursday.
It looked for a long period as if Jeonbuk would be the ones advancing to the semis, the winners of the AFC Champions League leading thanks to Kim Bo-kyung's well-taken goal midway through the opening period.
But Romero - who had struck the crossbar shortly after Kim's opener - scored twice in a 16-minute spell in the second period to send America through and leave Jeonbuk with the questionable consolation of a fifth-placed play-off against the other losing quarter-finalists.
America started brightly, but captain Oribe Peralta wasted two good chances and his side were made to rue those spurned opportunities.
Somewhat against the run of play, Park Won-jae got in down the left and squared for Kim to sweep home first time.
Jeonbuk goalkeeper Hong Jeong-nam produced a fine save just after the half hour, tipping Romero's dipping 30-yard effort onto the crossbar and Kim went agonisingly close to a second when he fired narrowly wide.
America began the second period in much the same fashion as they had the first and levelled matters just before the hour when substitute Michael Arroyo crossed from the left and Romero glanced home.
Peralta was then superbly denied by Hong, but from the subsequent corner the ball fell to Romero and his effort struck Choi Chul-soon and Kim Shin-wook before rolling beyond the goalkeeper to send America through to meet Madrid.