Bayern Munich left it late to continue their perfect start to the season with an 88th-minute Joshua Kimmich strike earning them a 1-0 win in Hamburg.
The hosts gave as good as they got for an hour, but they could not ultimately keep pace with their guests and spent the last half an hour holding on desperately for a point.
They were just two minutes away from doing so before Kimmich struck to seal Bayern's fifth successive Bundesliga win - and eighth in a row in all competitions - this season to leave Hamburg on just one point, with their coach Bruno Labbadia's future still uncertain.
Labbadia was under pressure after Hamburg's poor start to the season, but his team showed they were willing to fight for him.
Nabil Bahoui had the first shot of the game, which was too close to Manuel Neuer to trouble him, and Bobby Wood was a menace too as the hosts showed no fear of their league-leading guests.
Robert Lewandowski headed Bayern's first chance of the game onto the roof of the net, but it was only a rare opportunity for the league's joint top-scorer.
Wood had another chance for Hamburg, who would perhaps have been the more disappointed of the two sides to go in at the break goalless.
The tone of the game changed almost immediately in the second half with Bayern looking more their usual selves, creating chances and going close to opening the scoring when Rene Adler made a fine save from a dangerous Thiago Alcantara corner.
Bayern were appealing for a corner when Lewandowski went down under Emir Spahic's challenge after entering the penalty area, but the referee waved play on.
Ancelotti sent on Franck Ribery, who had been inspirational in the 3-0 win over Hertha Berlin in midweek.
The Frenchman brought more life to Bayern's attacking play, but Hamburg held firm at the back, built on the solid foundations of an inspired Adler between their posts.
He made excellent saves from Kimmich and Lewandowski before Labbadia decided to shut up shop, taking Wood off and bringing the defensive Michael Gregoritsch on for the final five minutes.
The move backfired with Bayern breaking the deadlock with just two minutes remaining, with Kimmich meeting Ribery's cross at the far post.
Pierre-Michel Lasogga was sent on for Albin Ekdal as Labbadia changed his tactics once again, this time in a bid to rescue a point.
With Adler up in support for a late corner, it was Lasogga who headed the last chance of the game over the bar as Hamburg were beaten and Bayern won once again.
ends