The second leg of the UEFA Champions League Round of 16 tie between Paris Saint-Germain (PSG) and Barcelona was an incredibly negative game. That's not to say it was bad but, at the risk of being jazzy, it was defined by what did happen, the tactics that didn't work and the goals that weren't scored.

Barcelona needed to overturn a 4-1 deficit away at the Parc des Princes and, judging by the team he picked, manager Ronald Koeman knew the main weakness exposed by the previous leg was how old his squad was. He took Pique out of the starting XI and used a 3-4-1-2 formation in which the star players had at least one younger, faster partner to link up with.

In the first half-hour, this proved fairly successful. It also exposed how thin Barcelona's bench is. This is the most important game in their season and Koeman has to play rookies such as 18-year-old Pedri and 20-year-old Sergino Dest in midfield; upfront, Lionel Messi was paired with Ousmane Dembele, 10 years his junior, and looked ancient.

In the 25th minute, soon after Dest rattled the bar, Barcelona mounted an attack with Dembele up the left. He got to the box and sent the ball across the face of goal but Messi was too slow to get there.

Barcelona had plenty of these chances. PSG were treating their three-goal cushion as infallible and taking things too easy. Having squashed the La Liga side in their own stadium last time, Les Parisiens didn't consider them a threat which speaks volumes to how much Barcelona have dwindled these past few seasons.

It got worse for Barcelona when they gave away an easy penalty only a few minutes later. VAR showed Clement Lenglet stood on the back of Mauro Icardi's foot in the penally box. Kylian Mbappe seeped up to take it; much less impressive than his hat-trick at the Camp Nou, it was still an important goal. 5-1.

The final 10 minutes of the opening half showed the best and worst of Messi. He received the ball outside the PSG box and must have seen something nobody else did. He took two quick steps forward and launches the ball into the net. The speed and the curve of the ball flummoxed everyone, including keeper Keylor Navas who barely moved.

1-1 now on the night, Barcelona got a pep in their step and PSG didn't know how to handle it. They had got used to three footballing halves of dealing with a plodding pace. Before the stroke of half time, Layvin Kurzawa scrambled to prevent Antoine Griezmann from receiving a cross in the PSG box and fouled him, giving Barca a penalty instead.

Messi stepped up to take it. Having produced magic minutes ago, surely he could do it again. He went to the same side as before (left) and sent it low. Navas read it the whole way and blocked it with his body.

This will have given PSG confidence at half time and they came out the other side. They continued to handle business without too much trouble and, in light of this potential Barcelona comeback, manager Mauricio Pochettino made a double substitution in the 59th minute: Angel di Maria for Julian Draxler, Danilo Pereira for Idrissa Gueye.

This was a move to show, not just that he wasn't concerned, by bringing on fresh attacking players, he believed one more goal from his side would put Barcelona out of range completely.

Once again, he was relying on Barcelona to be too out of sorts to mount a genuine threat and he was proved right. Barcelona's inability to string more than one offensive movement together was remarkable. So many times Barca had everyone forward with Jordi Alba or Dembele crossing in from the left, only for it to end with PSG intercepting and clearing or for the ball to miss everyone and sail into safety.

It ended 5-2 on aggregate. PSG go through, Barcelona go home and even though it's not a demo job on the same scale as what Bayern Munich did to them last year, in many ways it's even worse. Barcelona were once the most feared team on the planet, now they're handled with ease.

Ronald Koeman and his team will rue the mistakes they made. At first, they will be focused on the sloppy passes and dated tactics, only later will they stop to think that the biggest mistakes came months, years ago. Barcelona are a side that need a root-and-branch reboot and whether they get it will be down to what happens with Messi at the end of the season; his moments of magic no longer outweigh his mountains of mediocrity.