After losing at Brighton two weeks ago, Liverpool and Slot would have hoped that the international break would have provided the reset required before one final push until the end of the season.
The announcement that Mohamed Salah will leave in the summer, while significant, was not a surprise and had the potential to galvanise fans and players alike to give a club legend a memorable send off.
On top of that, the return of club-record signing Alexander Isak to team training after more than three months out provided another boost.
But 92 minutes in Manchester quickly did for any such optimism, with the number of potential trophies that might garnish Salah’s farewell swiftly halved.
Even a consolation goal was beyond them as Salah saw his second-half penalty saved – a moment Slot admitted “probably sums us up today and probably large parts of our season”.
“To get embarrassed like they did today is going to stick with them,” ex-Aston Villa striker Dion Dublin added on BBC Radio 5 Live.
Difficult as it is, though, Slot must find a way to rally his players before kick-off in Paris on Wednesday evening.
Another abject defeat could end Liverpool‘s hopes of progressing even before the second leg, at which point the season would become solely about trying to scrape back into the Champions League next season.
For all the mitigation that Slot can point to for the issues this season – injury problems, a severely disrupted pre-season, an unbalanced squad and, above all, the tragic death of Diogo Jota – failure to do so would leave him extremely vulnerable.
“We have to react to this defeat and this disappointing season,” he said. “There is a chance for us on Wednesday. We have shown today for only 35 minutes that we can compete.
“We can take positives from those 35 minutes but if we defend like the 20 minutes afterwards we will have a big problem. That is what we have to address.”
Time is fast running out for Slot to find those solutions and salvage something from Liverpool‘s season.
What that means for his future remains to be seen but those joyous scenes of last spring certainly seem a long time ago now.