The pirate flag is flying in the Bundesliga again.

St. Pauli returned to Germany’s top division after a 13-year absence on Sunday with a 3-1 win over relegated Osnabrück in the second division.

Oladapo Afolayan scored twice and set up Marcel Hartel for St. Pauli’s third goal as the home team moved top of the league with an unassailable six-point lead over third-place Fortuna Düsseldorf with one round remaining.

At the final whistle, St. Pauli fans stormed the field at the club’s Millerntor Stadium — a short walk from Hamburg’s famous red-light district — getting the party underway beneath a clear blue sky.

“I’m so happy for the team, for the whole city. We’ve earned it,” St. Pauli coach Fabian Hürzeler said. “I’m very, very happy to be able to coach this team. The success comes from hard work.”

The pirate skull-and-crossbones is synonymous with St. Pauli, popularized by fans who identified as punks. It was first carried by squatters who lived nearby and became a hit when the supporters opened an independent fan shop in 1989. The club eventually purchased the licensing rights in 2000 and co-opted it as an official emblem.

Supporters are still left-wing, known to sympathize with the poor and less fortunate in society, though divisions among fan groups have emerged this season because of Israel’s ongoing war in Gaza.

This is St. Pauli’s sixth promotion to Germany’s Bundesliga after 1977, ‘88, ’95, 2001 and ’10. The club lasted just one season on its last appearance before it was relegated in 2011. Next season will be its ninth altogether among Germany’s best, and it will be the first time that the cult club from Hamburg will play in a league above city rival Hamburger SV.

Hamburg, the longest surviving founding member of the Bundesliga — founded in 1963 — was finally relegated in 2018 after several close shaves. It lost 1-0 at Paderborn on Friday, ensuring it will spend another season in the second division as it can no longer finish among the top three.

The top two In the division are promoted, while the third-place finisher – now certain to be Düsseldorf – faces a two-leg playoff against the team that finishes third from bottom in the Bundesliga — currently Union Berlin — to see which will play in the top division next season.

The playoffs are scheduled for May 23 and 27.

Holstein Kiel, one point behind St. Pauli, secured its first ever promotion to the Bundesliga on Saturday. AP