Mauricio Pochettino's mission at Paris St-Germain is to win the Champions League amid the talk he will be the next manager of Manchester United.
If the Argentine fails, that may be the end of him at PSG anyway, even if he wins the French title. If he succeeds, he might feel his work in Paris is done and that he can move on with grateful thanks.
This may just be a "win-win" for Manchester United as they move from caretaker to interim manager and on to a summer permanent appointment following the sacking of Ole Gunnar Solskjaer.
The Champions League is the one trophy to elude Pep Guardiola at Manchester City amid a blizzard of domestic domination. That absence was felt most painfully when they lost last season's final to Chelsea in Porto.
But barring something unforeseen, Guardiola's future at City is as rock solid as he wishes, which cannot be said of Pochettino in Paris.
There was certainly temptation to highlight a contrast between Guardiola's bastion of stability and Pochettino's relative uncertainty as City secured top spot in their Champions League group with a fully deserved 2-1 win over PSG at Etihad Stadium.
City's manager spoke glowingly on the eve of this game about his personal and professional relationship with director of football Txiki Begiristain, one that goes back to their playing days together at Barcelona. Meanwhile, the speculation in Paris is about the perceived unease between Pochettino and sporting director Leonardo.
Guardiola's Manchester City were everything Pochettino likes his teams to be and more besides. for a start, they were actually a team.
City were a coherent, fiercely committed unit playing in the very specific style their manager demands. PSG were a collection of talented individuals with many marching to their own beat.
Guardiola's team has world-class players but they all work within that familiar high-intensity framework, allied to the sort of character that allowed them to shrug off the blow of going behind against the run of play to turn the game around.
Kylian Mbappe, Lionel Messi and Neymar had the fewest touches of the PSG players to play the full 90 minutes
PSG almost operate like two teams locked within one. There are Lionel Messi, Kylian Mbappe and Neymar - and then there's everybody else.
Pochettino's teams usually have his philosophy stamped right through them. Positive, athletic, pressing, intense. Every player imbued with a relentless work ethic.
Not this one.
The growing feeling, as the PSG fans made their discontent known at the final whistle, is that Pochettino's long-term hopes rest on somehow imposing his style on individuals who like to do their own thing. On this evidence, he has a job on his hands.
On several occasions, PSG's men at the back were seen gesturing to those at the front to get their hands dirty as City turned up the pressure. Those pleas that often fell on deaf ears. Too often, the big three were just strolling around and the rest were not good enough to carry them.
Messi, Mbappe and Neymar have all those glorious gifts but work-rate was not one of their qualities here. And, deep down, you can imagine that Pochettino's natural instinct is to want so much more.
Mauricio Pochettino was appointed PSG manager in January
In these circumstances, with these players, Pochettino could struggle to impose his style. PSG do not look or play like a Pochettino team.
If he does not, or cannot, do that, then talk of his arrival at Manchester United will only grow louder.
City were everything PSG were not. Pochettino must have looked on in envy as City's players showed sweat-stained character and resilience as well as class. And it was all done without Kevin De Bruyne, Phil Foden and £100m summer signing Jack Grealish. If calling this a statement win should be avoided, it was certainly a statement of strength in depth.
It is a mystery how the Champions League title has escaped a side as good as City but the talk of "statement" wins that usually follows these results is wasted now because too often it has been followed by disappointment. Their quest is quite simple. Win it.
When they play like this, they take some stopping. But we have said this before.
Taken on this game, however, City were the complete package. They imposed their will on PSG from the first whistle, pushing the French league leaders back, but they were hit with a sucker punch when Mbappe pounced on Messi's deflected cross.
PSG had asked the question of City and received an emphatic answer. Raheem Sterling capped a period of pressure with the equaliser and Gabriel Jesus scored the winner after Neymar missed a perfect opportunity to restore PSG's lead.
Once again, City showed they are perfectly at home among Europe's best. They must be placed with Chelsea, Liverpool and Bayern Munich in an elite group who can believe that Europe's most prestigious trophy can be theirs.
Pochettino cut a frustrated figure at the final whistle, disappointment written over his face at PSG's performance and the result.
Guardiola, in contrast, was a picture of delight at the end of a contest between Manchester City's team and PSG's individuals. The team won convincingly.