Five added minutes had just flashed up on the scoreboard when Jurgen Klopp wearily turned his back on the action and trudged to his seat.
He had seen enough. Liverpool’s manager had spent most of the game with arms outstretched like a scarecrow, screeching his fury, but it had been pointless. Klopp’s team had been wretched.
As he sat down, his thoughts would have turned to how he can make sure Liverpool are not eliminated from the competition that means so much to them. One false move in their last two games, against Paris Saint-Germain and Napoli, and the Reds could be out.
That is the reality following an abysmal 90 minutes in Belgrade, which ended with a superb Red Star side recording their most famous win at this level — thanks to two terrific, unanswered Milan Pavkov goals — since they lifted the European Cup in 1991.
Perhaps Liverpool thought it was going to be a formality. Klopp would never entertain that suggestion and the players would deny it, but this was a display that invited such stinging criticism.
The contest would surely have been different if Daniel Sturridge had snaffled the kind of opportunity in the 17th minute that you would expect him to convert with his eyes closed.
It was at the end of the one Liverpool move before the break that had any fluency. The ball went down the left, from Adam Lallana to Sadio Mane, and the forward’s cross squirted past Andy Robertson to Sturridge. His shot from six yards was high and horrible.
Their first goal arrived following a mistake by Virgil van Dijk, usually a figure of such calm and poise. He fluffed a clearance to Ben Nabouhane, whose shot from 20 yards was turned away by Alisson. From Marko Marin’s resulting corner, Pavkov plundered the first of his two goals.
If that was bad, worse was to follow. Liverpool’s midfield was getting overrun, but the feeble way in which Gini Wijnaldum was brushed aside after James Milner had squandered possession deserved punishment and Pavkov duly obliged.