Liverpool manager Jurgen Klopp admitted he did not feel the best after waking up the morning after the Reds' sensational 4-3 win over Borussia Dortmund that booked their place in the Europa League semi-final.
The Reds came back from 3-1 down to progress to the last four of the competition, with Dejan Lovren's stoppage time header securing their passage through to the semi-finals, and Klopp's name was written into Liverpool European folklore.
He told UEFA.com: "The morning after the game was completely different because usually after a match like that, you wake up and you think: 'Oh great, what a wonderful thing.' This time I was not in the best shape, to be honest, and I had no real idea why, and then I realised: 'Ah yes, they lost.'
"I had seven wonderful years at Dortmund and I knew how they felt. I knew what they would have done in the hotel and how it would have been when they woke up and all met for breakfast. I knew what the mood would have been like."
It was only in the summer when Klopp departed Dortmund, so there is still an element of attachment to his previous club. He felt bad that they were on the end of things, and he even went over to applaud his former club's supporters at the end of the game that night.
On Wednesday evening he has an opportunity to put his side in a good position for the second leg of the semi-final, and aim to reach the second cup final of his tenure after only six months in charge at the club.
If he were to end up winning the competition, one doubts that he will be feeling too bad about knocking out his old friends in the quarter-finals. If anything he may look back on it as one of the defining nights early on in his managerial reign at Liverpool.