There are times when the whole 'is Lionel Messi the greatest ever' debate seems a little silly.
The leagues, the Champions Leagues, the goals, the international finals - lost mainly on account of Gonzalo Higuaín being unable to hit a barn door in major finals - should really be enough proof for anyone by now.
But, when the unthinkable happens and Messi stops being a footballer and somebody has to add the word 'former' onto his Wikipedia page, it will be the performances rather than the numbers that people look back on.
And, in early March 2012, Messi came up with one of the displays that we will look back at and wonder why we ever even asked. Barça were defending their Champions League crown, and Bayer Leverkusen were the unlucky prey who wandered into the lion's den at the Camp Nou.
Early warning shots from bloodthirsty Barça
3-1 down from the first leg, Leverkusen didn't have a great deal to lose in the away tie. Barça were out to make a statement, and went into the game with little to no pressure on their gilded shoulders.
The warning signs were there for the visitors from an early stage. A Cesc Fábregas chipped pass over the top was chested down and volleyed hard towards the near post by Messi in the opening minutes, but Bernd Leno reacted well to strongly palm the ball away.
Soon after, Gerard Piqué nodded a Xavi free-kick towards goal when criminally unmarked in the penalty area, but Leno again made a firm save.
With 25 minutes played, though, the floodgates opened. They weren't battered down so much as delicately removed from their hinges by a master craftsman, as Messi chased down a long ball from Xavi down the left channel, raced clear on goal and scooped an impudent effort into the far corner. Leno didn't bother trying to save it.
20 minutes passed, and Messi had his second of the game, and his 50th of the season. Andrés Iniesta found him with a pass out to the right this time and, drifting along the edge of a congested penalty area, picked his moment to pull the trigger and pick out the bottom left.
Leverkusen collapse after the break
2-0 down at half-time, things were looking bleak for Leverkusen, but there was little that manager Robin Dutt could do to stem the flow. By the time the game reached the hour mark, two had swiftly become five.
This was in spite of Leno who, despite going on to concede seven, was one of the better performers on the night. He saved again from Fábregas and Pedro, standing up well to two close-range efforts, before Messi completed his hat-trick less than five minutes into the second half.
It was close to a carbon copy of his first goal - Fábregas over the top of the defence, Messi over the top of the goalkeeper into the far corner, nothing Leverkusen could do to stop it and Messi's 10th Champions League goal of the season.
Leverkusen went close to a consolation goal soon after as Eren Derdiyok took the ball around Víctor Valdés and attempted a chip of his own from a tight angle, but the Swiss international's effort bounced across the face of goal and was hacked clear.
Cristian Tello got in on the action soon after. The La Masia youth product was on the pitch as a substitute and, streaming down the left, chose to glide the ball around Leno and into the bottom right corner rather than pick out a teammate.
It was a superb finish during a performance which many hoped would announce the Barcelona youngster as a future star. The goal came within a minute of his coming on - and inside his first minute playing on the European stage.
Leno lapse gives Messi his fourth
Leverkusen were clearly flagging at this stage and their defence was left chasing shadows as Messi exchanged a one-two, then a three-four with Pedro at the edge of the area.
Leno did what he could to paw the pass away from the onrushing Argentine but it wasn't enough, Messi grabbing his fourth of the night by tucking the rebound in at the far post from a tiny angle.
The goalkeeper was at fault for the goal for the first time on the night, and it seemed to be still on his mind as Tello found himself in space again. The young Spaniard went for the same far corner and beat Leno, who could only divert his shot into the back of the net.
Seydou Keita was nearly an unlikely name on the scoresheet next, as Pedro looked to pick him out with a square ball across a penalty area which seemed abandoned by German defenders.
His pass was just out of reach for the Malian midfielder, but it was a clear sign that Barça had no intent of letting up. Keita went close again soon after from a corner.
Messi makes history with five
He didn't get a goal that night but Keita did at least get to be a part of history as he assisted Messi's fifth - the first time a player had scored five in the Champions League.
This one was the most simple of the bunch - a reverse pass from Keita at the edge of the area to find Messi, who bent the ball around Leno into the bottom corner once more with that stroke of the left boot that only he possesses, as if it was the easiest thing in the world.
Leno made a fine save to deny Tello a hat-trick of his own and Karim Bellarabi stroked a delicious finish past Valdés at the other end in stoppage time to give the travelling fans something to cheer, but it was clear that the game had been yet another chapter in the Messi story.
Barça went on to beat AC Milan in the next round before being knocked out by Chelsea in the semi-finals of their very own fairytale story, but Messi's performance that night against Leverkusen was of a level rarely seen in the history of football.
Clive Tyldesley said that those present were "in the presence of greatness", in a summing-up of the night that didn't quite do it justice - but whether there truly any words of enough grandeur that could have been spoken is another question.
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This is part of a weekly feature series, 'Classic Matches Revisited'. Catch up on last week's entry, on one of the finest North London derbies in living memory, here.