Manchester City midfielder Ferran Torres netted a hat-trick in the stunning rout which meant the Spaniards leapfrogged Die Mannschaft into top spot in Group A4.
The shell-shocked Germany only required a draw in the match after Spain stumbled with a 1-1 draw against Switzerland on the weekend, but La Roja were in a merciless mood in Manuel Neuer’s record-breaking appearance as his country’s most capped goalkeeper.
Neuer was beaten six times, including conceding three goals inside the opening 38 minutes, firstly from Alvaro Morata in the 17th minute, before goals to Man City pair Ferran Torres and Rodri in quick succession.
Gaya set up Ferran Torres for his second in the 55th minute before he curled home on a break from a Fabian Ruiz pass to complete his hat-trick in the 71st minute.
Serge Gnabry cannoned a shot into the woodwork for Germany, only for Gaya to lay off for Mikel Oyarzabal for the sixth, which sealed an all-time competitive low for the Germans.
Germany midfielder Toni Kroos told ARD post-game: “It’s probably not the most bitter defeat of my career, but surely one of the biggest.
“It hurt. We did not get any grip on them. Spain showed us how to attack.”
The result has heaped pressure on Germany boss Joachim Low, after his side missed out on the Nations League semi-finals fresh from their dismal showing at the 2018 World Cup where they finished in their group.
Elsewhere on Tuesday, Switzerland and Ukraine’s match in Luzern in Group A4, which would determine who’d be relegated, was postponed after more positive COVID-19 cases among the visiting squad.
In Group A3, Ruben Dias netted two goals, including a late winner, as Portugal triumphed 3-2 away to 10-man Croatia, while Sweden were relegated after a 4-2 loss to world champions France who had Olivier Giroud score a double.