The flight back from Macedonia in the early hours Wednesday would have left Manchester United boss Jose Mourinho with plenty to ponder.
Here are some key issues to address…
UEFA’s pre-match teamsheet put Manchester United down in a regulation 4-3-3 formation, but soon after kick-off it was apparent that the summer’s 3-5-2 experiment had continued.
Although not discouraging, the results of this weren’t overwhelmingly positive.
There appeared to be confusion in the ranks in regards to pressing, while a bright start quickly ebbed away.
Mourinho must now settle on a tactical plan – like Antonio Conte plus, latterly, arch-nemesis Arsene Wenger – and stick to it.
In the fallow years since Sir Alex Ferguson departed, premier occasions have become the exception rather than the norm.
Thus, real encouragement can be taken from the fact United were not utterly outclassed by the Champions League holders.
The burning issue now is how can Mourinho close the gap even further?
An elite attacking threat from the left flank is a must, with Real Madrid’s Gareth Bale a pipe dream.
If 3-5-2 is the way forward, upgrades at both wing-back and centre-back must occur.
Paris Saint-Germain rightback Serge Aurier has been linked, while could there yet be a twist in the race for Southampton’s wantaway centreback Virgil van Dijk?
These marquee matches are the ones Paul Pogba was brought back for at an eye-watering – then – world-record price.
This was not as disastrous as Liverpool at home last term, but the France superstar was either peripheral, or too selfish on the rare occasions he was involved.
Worryingly, this sketchy display came from his favourite position drifting to the left of midfield.
Mourinho must dig into his legendary reserve of psychological techniques and tactical knowledge to formulate a way to get Pogba firing.