Jaime Mata scored a penalty in the 56th minute after Allan Nyom was brought down inside the area by Frenkie De Jong, handing the Azulones their first win over the Catalans since 2007.
Meanwhile, this was another disappointing performance for Barcelona. They didn't create many chances and proved wasteful when two clear-cut opportunities showed up. Lionel Messi, who had a relatively quiet game by his standards, even hit the post.
The defeat means Ronald Koeman's men failed to capitalise on Real Madrid's own setback earlier in the day and drop to ninth place on the table with only seven points from the opening four games.
Here are the major talking points from the game:
#1 Barcelona's French duo disappoint again
Antoine Griezmann and Ousmane Dembele together cost Barcelona a whopping €325 million and yet, neither have truly justified their hefty price tags.
Griezmann offered little in the way of attack and also had the fewest touches of all Barcelona players. But that's not all; he missed a golden chance to put his side ahead in the first half by firing his shot over the bar with only the goalkeeper to beat!
Dembele, on the other hand, lacked ball control. He was dispossessed on way too many occasions (16 to be precise, a game-high) and often looked clueless on the left flank.
Could this be due to the fact that this was his first start for the club in almost a year? Maybe. However, Dembele still needs to improve massively if he wants to prove his worth to the team.
#2 Getafe's high press throws Barcelona off track
Barcelona hadn't lost to Getafe in the league since 2007, so this was touted to be a walkover for the Catalans. However, the latter had other plans.
El Geta came flying out of the blocks, much to the surprise of the mighty visitors, and took the game to them with some high pressing.
Much of the threat stemmed from the right flank with Damian Suarez and Allan Nyom making forays to link up with Mata and Cucho Hernandez. Even though clear-cut chances were hard to carve out, Barcelona were clearly rattled by Getafe's pace and quick passes.
They conceded some cheap fouls while Neto had to make some important saves to keep the tie level. However, nerves got the better of them in the second half when Frenkie De Jong hacked Allan Nyom down inside the area after the defender tried to connect with Djene Dakonam's pass, conceding a penalty which Mata coolly dispatched.