A fixture worthy of the final, and a goal fit to win any game of football.

Paris Saint-Germain versus Real Madrid was billed as the tie of the round of 16, the Champions League kings against the would-be usurpers, old money versus new. More than that, it was the match to decide the future of Kylian Mbappe: parent club and suitors, battling for the right to call him their own next season. It was the sporting equivalent of a divorced couple fighting over the family dog, waiting to see who he runs to.

At full-time, it was 1-0 to PSG, a deserved win at the end of probably their best performance under Mauricio Pochettino. It was Mbappe, of course, who scored the goal at the death, reminding home and away teams why getting him to sign their contract might be the most important thing they do for years.

This tie and that tale are far from over.

The word from Spain is that Mbappe's signing is as good as done. Indeed, he might as well play with a Madrid shirt concealed underneath his PSG colours, ready to tear off the disguise and reveal his true identity as Florentino Perez's latest galactico. You can already see the Superman segment on El Chiringuito.

In Paris, they whisper a different story, one in which Mbappe may yet be convinced to sign a new deal and fulfil his dreams in his home city alongside Lionel Messi and Neymar.

The truth is nobody but Mbappe knows for certain what he wants to do, but there was an undeniable feeling on Tuesday that he might have outgrown his surroundings. Already the best player in France, perhaps he sees lighting up LaLiga as the next logical step towards a football legacy.

Kylian Mbappe carries in PSG 1-0 Real Madrid

When Barcelona pulled off that incomprehensible comeback against PSG five years ago, Neymar was the star. It was his three-minute double that pushed Barca to the brink of an impossible 6-1 victory, and his pass to Sergi Roberto that delivered it. Yet it was Messi who took centre stage in the club's post-match footage and imagery; according to some reports, thus were sown the seeds of Neymar's longing to break free of Camp Nou shackles, ending in that €222million transfer.

It was hard not to think of that as Mbappe, midway through the second half here, watched Messi take and miss the penalty he had won.

If this really was the 'Mbappe derby', he looked happy – even determined – to embrace it as such, even if that wasn't always the best course of action. He skipped and step-overed his way into the box and shot straight into a packed Madrid defence when the cut-back to Messi was obvious. He led poor Dani Carvajal a merry dance, charging straight at him or cutting infield, the full-back little better at guessing his next move than the thousands of spectators who cheered his every touch. Just past the hour, Carvajal gave up on subtlety and decided hurling himself into the forward's legs was the only way to stop him. The only surprise was that Messi, not Mbappe, took the spot-kick that was saved by Thibaut Courtois.

For all Mbappe's efforts, there was no breakthrough. Madrid had defended stoutly, their attempts to attack given up in the opening minutes. David Alaba and Eder Militao marshalled the rearguard expertly, and Courtois showed why he is probably now the world's best goalkeeper. Even Neymar's first appearance since November could not breach the barricades, although they certainly creaked with every blonde-haired burst forward.

But of course Mbappe had the final say, and with practically the final kick. Neymar backheeled it, Mbappe flowed fleet-footed through a gap, and the ball was beneath Courtois via a tiny, telling deflection before his long legs could hit the ground. It was a 94th-minute winner, delivered with the speed and precision of the first move of a training session.

Mbappe wheeled away, arms outstretched, team-mates chasing in his wake, the Parc des Princes a living roar. His moment, his night, his team. But which one?