Carlo Ancelotti has admitted showing his middle finger to Hertha Berlin fans he accused of spitting at him after Bayern Munich's 1-1 draw in the German capital on Saturday.
With Bayern trailing to Vedad Ibisevic's 21st minute goal and the allocated five minutes of added time already played, substitute Robert Lewandowski salvaged a point for the league leaders with the last kick of the game.
Lewandowski's 16th league goal season -- timed at 95:59 -- was the latest goal in Bundesliga history since detailed records began in 2004-05.
But in ugly scenes following Lewandowski's dramatic last-gasp equaliser, Hertha's goalkeeper Rune Jarstein kicked the ball into Xabi Alonso's back from close range, leading to an on-pitch melee between the two teams.
Goalkeeper Manuel Neuer, in attack for the late free kick from which Bayern grabbed their goal, said: "That has nothing to do with fair play, it doesn't matter how frustrated you are. There's a massive crowd here and it's not setting a good example."
And Hertha fans are alleged to have spat at Bayern boss Ancelotti as he was going down the tunnel towards the dressing rooms. The 57-year-old Italian reacted by extending his middle finger to the offending parties.
Speaking to ARD Sportschau after the game: "Yes, I made this gesture as I was spat at earlier."
DPA news agency and Kicker magazine say the German soccer federation (DFB) is investigating Ancelotti for the gesture, while kicker reports that Jarstein has also been asked to explain his actions.
In 2014, Norbert Duewel, then coach of second division Union Berlin, was fined 3,500 euros for showing his middle finger in a 4-1 defeat at home to 1860 Munich.