But the 29-year-old was unimpressed at how Die Mannschaft defended at the Luzhniki Stadium, admitting that the players had ignored warning signs that arose during warm-up matches ahead of the tournament in Russia.
A solitary goal from PSV Eindhoven winger Hirving Lozano, who is tipped by many to become a household name with his performances at the World Cup, was enough to give Mexico the shock win on Sunday, although El Tri did have to survive a barrage of attacks throughout the match.
Hummels admitted that Mexico did deserve to beat the reigning champions on Sunday, but the Bayern star was furious that Germany hadn't identified their weaknesses ahead of the tournament this summer.
"Mexico deserved the win. Our cover was often not good and we were left many times with Jérôme [Boateng] and myself at the back," Hummels claimed, quoted by the Sun.
"That’s why the first half was like it was, and Mexico obviously deserved to win it.
"If seven of eight players are attacking then it’s clear our attacking power is greater. But that’s something that I have often talked about internally. It doesn’t always bear fruit.
"A wake-up call is too late. We now must win two games, otherwise, that is that with the World Cup. I don’t really understand why we played like we played because, really, we already had our wake-up call."
Germany were one of the favourites heading into the tournament, with many fans expecting that Die Mannschaft would retain the trophy following their success in 2014.
But Mexico have now given teams the blueprint of how to beat the World Cup holders.
El Tri camped in their own half for the majority of the game, not offering danger man Timo Werner any space in behind. That acted as the platform to launch a number of deadly counter-attacks which Germany were unable to deal with throughout the match.