RB Leipzig picked up a first Bundesliga win in their maiden home fixture as an 89th-minute Naby Keita strike secured a 1-0 win over Borussia Dortmund.
Mario Gotze made his first start since returning to Dortmund from Bayern Munich, while Scotland international Oliver Burke made his debut for top-flight newcomers Leipzig and set up their winner in Saturday's early-evening game.
Leipzig were founded in 2009 by the owner of the Red Bull empire, Dietrich Mateschitz, and their promotion to the Bundesliga has been bankrolled by the Austrian.
Leipzig forward Timo Werner said of the breakthrough win: "We have fought insanely and shown that we can compete. The atmosphere was unbelievable."
Joel Pohjanpalo was Bayer Leverkusen's unlikely match-winner as the Finland international joined Robert Lewandowski at the top of the Bundesliga scoring charts with a hat-trick at home to Hamburg.
The 21-year-old took his tally to four goals for the season after coming off the bench to make all the difference in a 3-1 win.
With Leverkusen trailing 1-0 to a Bobby Wood goal, Pohjanpalo headed them level 11 minutes from time before completing his hat-trick with two goals in stoppage time to earn his side all three points.
Maximilian Philipp was also on clinical scoring form on Saturday with his two goals helping Freiburg to a 3-1 home win over Borussia Monchengladbach.
Thorgan Hazard opened the scoring for Monchengladbach, who had won all four games they had played this season across all competitions, before Philipp's double and a Nils Petersen effort saw the Black Forest club take the spoils.
Philipp was joined on two goals for the season by Hertha Berlin's Julian Schieber, who scored late on for the second game in a row to tie up a 2-0 win at Ingolstadt.
Hertha joined Bayern Munich at the top of the Bundesliga with two wins out of two. Vedad Ibisevic was also on target for Pal Dardai's men.
Elsewhere, Sandro Sirigu scored his first Bundesliga goal as Darmstadt beat visitors Eintracht Frankfurt 1-0 in a Hesse derby, and Mario Gomez failed to find the back of the net on his return to the Bundesliga with Wolfsburg, who were held to a goalless draw at home to Cologne.