Thomas Muller converted the spot kick in the 90th minute after Diego Costa went down in the box, but the official admits he should not have awarded the foul

The referee who awarded Bayern Munich a late, decisive penalty in a 2-1 Bundesliga win over Augsburg has admitted that he got the decision wrong.Thomas Muller converted the 90th-minute spot-kick to maintain Bayern's perfect start to the season, after Robert Lewandowski had cancelled out Alexander Esswein's first-half opener.The penalty, described as a "joke" and a "catastrophe" by Augsburg head coach Markus Weinzierl, was awared after Markus Feulner was judged to have brought down Douglas Costa in the box.And, having watched the footage back, referee Knut Kircher has had a rethink."If something happens on the pitch and the linesman sees it, he has to give me a signal," he told Sportschau. "In this case, the linesman was convinced it was a foul."I could only see the situation from the corner of my eye, so I had to rely on my assistant's decision."We have now seen the footage and I must admit he got it wrong, so I got it wrong as well, because I am the one in charge."It does not give Augsburg any points, but we are sorry. Our decision was the wrong one."Even Bayern match-winner Muller conceded there were doubts over the awarding of the penalty, adding: "He, of course, blocks Douglas... I'd say that's a 50-50 story."