Ange Postecoglou appeared to be furious with a Tottenham fan as he walked through the tunnel after the defeat to Ipswich.
Spurs lost 2-1 to the Premier League newcomers on Sunday, with the Tractor Boys leading 2-0 thanks to Sammie Szmodics and Liam Delap before half-time.
Rodrigo Bentancu scored a consolation goal with just over 20 minutes remaining, but the visitors took all three points in the end and claimed their first top-flight victory since 2002.
Spurs fans expressed their feelings throughout, and sections of supporters booed the team at the final whistle.
Postecoglou walked down the tunnel with a stern expression on his face and his hands in his pockets.
But footage from the seats above the tunnel shows the Spurs boss stopping dead just before disappearing from view.
He seems bewildered by a comment heard from the stands to the left of the tunnel.
The Australian looks up and fixes his gaze on a particular place.
His staff soon followed suit to see what or who Postecoglou had focused on.
After holding the gaze for a few seconds, Postecoglou turns around and continues his way back to the locker room.
Despite his obvious frustration with a section of his fans, he was the owner of his team's fifth league defeat of the campaign.
“Ultimately, it's my responsibility,” he said in the mixed zone after the game.
“It has nothing to do with the players. The inconsistency we are having this year is due to me.
“I have to make sure we try to find a way to become a more consistent team.”
And he doesn't mind being booed by his fans either.
“The fans will be disappointed,” he added. “They have the right to be.
“Like I said, the onus is on me to fix it.”
Tottenham are now 10th in the Premier League standings.
Meanwhile, Ipswich have moved out of the relegation zone one point clear of second-to-last Crystal Palace.