Liverpool boss Klopp saw his side battle past Barcelona on a breathtaking night at Anfield, ensuring they reach the Champions League final for the second year in a row.
Few gave the Reds a chance of progressing after a Lionel Messi brace and Luis Suarez strike had put them to the sword in the first leg.
But Liverpool produced a stunning comeback, with braces from Divock Origi and Gini Wiljnaldum teeing up a final showdown with either Ajax or Tottenham later this month.
Many in the press area were expecting Klopp to be smiling non stop.
And though the Liverpool boss was happy, he managed to keep his cool.
The Reds boss politely swatted away a question about Barcelona and whether they had a problem performing under pressure.
“You would need to ask them,” he said politely.
The Liverpool boss did spend time emphasising how proud he was of his side, though, labelling it ‘special’.
“What they did was so special,” he said.
“I will remember it forever and I don’t know if it will happen again.”
One question was pitched to Klopp. Would Liverpool have beaten Barcelona if the game had been played behind closed doors?
There was no smile on his face. “No,” he said.
The Liverpool crowd were stunning on the night with Anfield a cauldron of noise as they dared to dream.
By the final whistle, the volume inside the stadium reached fever pitch.
Liverpool players were serenaded by a fanbase who had stuck with them throughout the tie.
Even at 3-0 down, there was a sense a job could be done. That Barcelona and Messi were not unbeatable.
Meanwhile, Ernesto Valverde’s own press conference was short. But not sweet.
The Barcelona boss masked his emotions throughout and answered questions from Spanish media. He did not appear to particularly like them.
Valverde’s head is now there for the taking. Will Barcelona wield the axe, or give him another shot at Champions League glory?
Klopp, meanwhile, will take his Liverpool side through to a second Champions League final in as many years.
And he will be back to his smiling, cheerful self if they manage to land the trophy he craves.