After three seasons in the second flight, Schalke's 1-0 home win over Fortuna Duesseldorf on Saturday returned the German giants to the Bundesliga.
For those inside the club, the road to promotion is about making good on a series of mistakes and bringing Schalke back where they belong.
Seven-time German champions Schalke are among Europe's best supported teams. Only two clubs in Germany – Bayern Munich and bitter rivals Borussia Dortmund – have more than their 200 000 members.
In 2021, Schalke were relegated for the first time in three decades. Saddled with debt, a Covid-era relegation hit harder.
After an immediate return to the top flight, they suffered the same fate again – and this time did not bounce back so easily.
CEO Matthias Tillmann, who joined the club in 2024, told AFP that Schalke being in the second division is a "mistake".
"We are not a second division club when it comes to fans, to infrastructure," he said.
"Obviously, we are there now and there are reasons for that.
"We've made mistakes on the sporting side, capital allocation... The first relegation in 2021, the beginning of Covid, was very tough financially.
"Then we immediately went down again, which is not good."
In 2022, the club took another financial hit with the termination of a lucrative sponsorship with Russian energy giant Gazprom after the Ukraine invasion.
'A NEW MINDSET'
Schalke's support has endured despite their lack of on-field success, with every one of their 16 home matches attracting over 60 000 fans this season.
But Schalke's size and history meant the club could feel crushed under the weight of expectation.
In 2024-25, Schalke spent much of the season close to the relegation spots, finishing 14th of 18 teams.
In summer, the club signed coach Miron Muslic and brought in Frank Baumann to head up the sporting department.
Baumann said Muslic helped Schalke rebound after their "worst season ever".
"In the past couple of years, maybe (the players) were afraid of the reaction of supporters when they lose," Baumann told AFP.
"But this mindset, we changed in the summer. Miron, as head coach, had a lot of influence on this."
Tillmann admits the club's promotion was ahead of schedule, joking Schalke's pre-season aims were less lofty.
"Youri (Mulder), our sporting director, said it in a funny way, that our goal is that we don't have to fire our coach this year.
"So far we're on track. I don't think we'll do that in the next couple of weeks."
Tillmann said Schalke welcomed the "challenge" of going up earlier than expected.
"You cannot say, we are not quite ready, so let's not go up this year. We do it next year.
"That's not how it works."
Tillmann, a lifelong Schalke fan, took over in January 2024 after a career in the private sector.
"It's not a normal business," Tillmann says of football. "We're not here to make profits, to grow revenue – that's only a means to an end.
"We have all of this to build a great squad, to win trophies."
'YOU HAVE TO WIN'
Recruitment has also been key. Schalke signed veteran striker Edin Dzeko in January.
Remarkably, Schalke were top of the table at the halfway point having scored just 22 goals in 17 games. Only six teams in the division had scored fewer.
Dzeko's six goals and three assists in nine games have been crucial.
Baumann said Dzeko could have earned "much more money" elsewhere, but wanted to join the club.
Walking across the turf with a beer on Saturday, Dzeko said he hoped to stay at the club.
"You never want to stop playing. I don't want to stop, football is my life," Dzeko said to Sky Germany, adding "but first we can celebrate and have a few drinks...
"After that there will be time to sit down together."
A Schalke return to the top flight also means the stage is set for regular Revierderby clashes with Dortmund, perhaps the biggest derby in German football.
"It'll be my first derby against Dortmund, so I'm very excited. But you don't just play a derby, you have to win. That's more important," Baumann said.