Hernandez would not be denied again, though, the West Ham striker making no mistake in drilling in his landmark goal to send the raucous Mexican crowd into raptures.
South Korea: Jo Hyeon-woo, Lee Yong, Son Heung-min, Ju Se-jong, Hwang Hee-chan, Kim Min-woo, Ki Sung-yueng, Kim Young-gwon, Jang Hyun-soo, Lee Jae-sung, Moon Seo-min.
This time, the roles were reversed as Hirving Lozano led the charge up the field before feeding a pass to Hernandez, who calmly skipped inside a defender before finishing into the back of the net.
However, it was not enough for the South Koreans as Mexico and Juan Carlos Osorio bagged all the points.
Löw had rung the changes before the game, bringing Reus and Sebastian Rudy into the starting line-up at the expense of Mesut Ozil and Sami Khedira - the first time the Germany coach has left the Arsenal midfielder out of the starting XI at a major tournament since 2008.
Hernandez added the second in the 66th, scoring his 50th goal for Mexico.
Mexico is in almost complete control over South Korea at halftime at the World Cup despite just a 1-0 lead courtesy of a Carlos Vela penalty kick. But history was not on Mexico's side because it had not won back-to-back matches at a World Cup since 2002. As if anyone didn't know it, Son is the team's best player by a distance.
- South Korea has conceded a goal via a penalty in both of its World Cup games so far in 2018 - in its previous 29 World Cup games combined, South Korea conceded only one penalty goal.
"We didn't listen to the criticism", said Javier Hernandez, one of the scorers against South Korea. Heung-Min Son scored in the stoppage time to half the deficit but in the end it was no more than a consolation.
Lozano and Vela then took it in turns to try their luck, but the former saw his goal-bound effort blocked before the latter curled over the crossbar during an open period of the match.