Germany defender Nico Schlotterbeck said his side were "playing with euphoria, playing with fun" after Saturday's 2-0 win over Denmark, which meant the Euro 2024 hosts reached the quarterfinals.
Schlotterbeck, drafted into the Germany starting XI after Jonathan Tah's yellow card, lauded his side's "super game", adding: "We've released something in this country.
"We're playing with euphoria, we're playing with fun and that's when football is the most beautiful."
The Borussia Dortmund defender had been left out of Nagelsmann's squad earlier in 2024 but was recalled as the German club went on a run to the Champions League final.
The match was delayed by 25 minutes in the first half due to thunderstorms and resumed shortly before halftime.
Denmark had the ball in the back of the net early in the second half but the goal was chalked off for a narrow offside, moments before Germany won a penalty, converted by Kai Havertz.
Germany's win was their first in a knockout game at a major tournament since 2016 and sets up a clash with the winner of Sunday's last-16 match between Spain and Georgia in Stuttgart .
"I'm really happy we kept a clean sheet, we defended unbelievably well and barely let anything in," said Schlotterbeck.
"We played a good game, rewarded ourselves with two goals and I'm hugely pleased.
"We had some crazy fans here today and the stadium was shaking – I know that from Dortmund, but not so much with the national team."
Germany defender Antonio Ruediger, named man of the match despite only training once in the lead-up due to a hamstring strain, had his eyes on the end goal.
"We still have three finals left," the Real Madrid defender told Magenta, saying Germany was "dominant from the start".
"This team shows good character, we can always come back, always give it our all."
Schlotterbeck said he was "incredibly looking forward to the game in Stuttgart".
"I grew up five kilometres away from the stadium. All my mates, my family, will come."