Ladislav Krejci put the Czechs ahead with a fine header as the European side dominated in the air, but Hwang In-beom equalised shortly afterwards and turned provider for substitute Oh Hyeon-gyu’s winner.
The Koreans joined Mexico on three points at the top of the pool after the co-hosts defeated nine-man South Africa 2-0 in the tournament opener in Mexico City.
South Korea next face Mexico next Thursday and the Czechs travel to Atlanta to meet South Africa on the same day.
