Three from three ... Eintracht Frankfurt players celebrate Stefan Aigner's goal (Getty Images)
Eintracht Frankfurt made it three wins out of three and spoiled Rafael van der Vaart's second Hamburg debut as the newcomer won 3-2.
Armin Veh's side signalled its intentions with two goals inside five first-half minutes from Takashi Inui and Olivier Occean.
Hamburg pulled a goal back on the stroke of half-time through Heiko Westermann, but it also lost Petr Jiracek to a red card before the interval.
Stefan Aigner gave Frankfurt a two-goal cushion to sit on in the 52nd minute, but Son Heung-Min made a game of it by scoring a second for Hamburg in the 63rd minute, setting up a tense finale in which Frankfurt held on to join Bayern Munich in a share of top spot.
There was more drama in the day's other game as Freiburg got the better of Hoffenheim 5-3 at the Dreisamstadion with the pressure increasing on the visitor's coach Markus Babbel.
The game started well for Hoffenheim with Matthieu Delpierre putting it ahead in the second minute, but Karim Guede and Max Kruse turned the game around before half-time.
Boris Vukcevic brought Hoffenheim level in the 57th minute before Fallou Diagne headed Freiburg ahead for the second time.
Hoffenheim refused to lie down and it equalised again through Takashi Usami in the 76th minute, but Cedric Makiadi and Sebastian Freis ensured Christian Streich's side was ultimately rewarded with all three points.