Michael Gregoritsch grabbed a late winner for Hamburg to leave Ingolstadt still waiting for their first home win of the season after going down 1-0 at the Audi Sportpark.Ingolstadt set a Bundesliga record for winning their first three away games in the top flight at the weekend, but their home form has been quite the opposite with Hamburg taking advantage on Tuesday night.Ingolstadt had looked strong with Mathew Leckie menacing, but it was Hamburg who struck after Johan Djourou saw a goal ruled out.Gregoritsch's goal came in the 87th minute and lifted Hamburg above Ingolstadt in the standings on goal difference.