Barcelona are finalizing preparations for their all important first leg vs. Liverpool on Wednesday when they’ll kick off a mouthwatering Champions League semifinal matchup against Liverpool.

Despite being a routine footballing Goliath, and a historically good run of domestic success, the Catalan club haven’t made it to this stage of Europe’s premier club competition since 2015 when they won the UEFA Champions League (and the treble, for good measure).

Barcelona’s last three Champions League campaigns have been characterized by quarterfinal flops — they lost to Atletico Madrid in 2016, Juventus in 2017, and famously, Roma in 2018 when they squandered a 4-1 aggregate lead to lose on away goals.

Point being, it’s been four years since Lionel Messi has played in a Champions League semifinal at the Camp Nou, a drought which will end when he takes the field tonight versus Liverpool.

It is worth remembering his last performance at this stage, at home– arguably the finest showing of Messi’s absurdly excellent career.

The date was May 6, 2015. Barcelona were taking on Bayern Munich in Leg One. Barcelona, similarly to this season, hadn’t made it to the final of the Champions League since 2011 when they took home the title by defeating Manchester United in the final.

The stakes of this match were unusually high for three reasons. Firstly, the occasion — while domestic success is nice, the Champions League is truly the bar that separates the good teams from the great teams.

Secondly, there was retribution in the air — Bayern famously annihilated Barcelona by a 7-0 aggregate score just two years before, before going onto win the title themselves. It was a rude awakening for a Barcelona team that lacked serious bite, against a Bayern side playing with typical German ruthlessness and efficiency.

Thirdly, it was a homecoming of sorts for Bayern manager Pep Guardiola, a Barcelona club legend both as a player and manager. Barca had been unable, in the years following Guardiola’s departure, to recapture the Champions League after winning it under his management in both 2009 and 2011.

With the stakes set high, it was evident that Barcelona’s outstanding front three of Messi, Luis Suarez, and Neymar would have to propel the Catalans past a Bayern team that had shamed them two years earlier.

What followed was, arguably, the best 20 minutes of Lionel Messi’s career.

The first 76 minutes of the match were tense, with each side failing to break down the other. Each side had a golden chance in the first half. Luis Suarez had a brilliant one-on-one opportunity against Bayern goalkeeper Manuel Neuer on the counter attack, but the German shot stopper denied the Uruguayan forward.

On the other end, a masked Robert Lewandowski scuffed a beautiful Thomas Muller cross that surely would have flown past a sprawled Marc-Andre Ter Stegen had it been hit cleanly.

Finally, in minute 77, a breakthrough. A careless piece of dribbling by Bayern left back Juan Bernat saw the defender get dispossessed by Barca right back Dani Alves who found Messi on the right hand side. Messi took a touch, and then, with a precision that even the most experienced sniper would be envious of, Messi ripped a low curled effort that beat Neuer (who at this point was, almost objectively, the world’s best goalkeeper) at his near post to give Barca the lead.

SEE MORE: Schedule of UEFA Champions League games on US TV and streaming

It was a magnificent goal despite it stemming from a defensive effort from Bernat. The awareness from Alves to pick the Spaniard’s pocket and to find Messi, and the magic man did the rest — it cannot be understated how difficult it is to beat a goalkeeper with Neuer’s frame at his near post, especially from outside the box. Messi made it look easy.

It took only three minutes for Barca to double their lead with a goal that will be remembered as one of Messi’s finest. Despite all his goals, only a handful are remotely comparable to this stroke of genius.

Ivan Rakitić found Messi on the right channel in space, and Messi went right at Jerome Boateng (who, similar to Neuer was one of the finest, if not the finest player at his position in world football).

Messi shimmied Boateng, leaning left before darting right, a movement so quick and controlled that it made the German defender twist and fall to the ground, seemingly paralyzed by the physics-defining shift in gravity. Messi left Boateng broken and helplessly laying on the grass, in his wake, before dinking an onrushing Neuer with a chip as audacious as it was beautiful.

It was the sort of goal that was stunning not just because of the skill — yes, the dribbling was amazing, the quick move on Boateng genius, and the chip daring — but the way that Messi embarrassed arguably the best center back and the best goalkeeper on Earth gave this goal another level.

As Martin Tyler put it from the gantry…

“It’s astonishing. It is absolutely world class… he’s taken them apart.”

And then:

“Only football can make you feel like this.”

A fair point. Seeing Messi’s second goal against Bayern was like seeing van Gogh himself paint the Starry Night, or Francis Ford Coppola direct The Godfather, or Einstein deducing the theory of relativity. You felt like you were genuinely witnessing a genius that was unrivaled amongst his peers, and that goal (which, coincidentally, put him ahead of Cristiano Ronaldo amongst the all time leaders in Champions League goals) showed just how immense the gap was between Messi and literally anyone else on earth.

A 2-0 deficit meant that Bayern had to begin to really chase the game, in search of an all important away goal to take back to Allianz Arena. As conventional football goes, when a team presses forward, they leave gaps at the back for teams to counter, which is just what Barcelona were able to do.

In the 94th minute, Luis Suarez picked up the ball in midfield before getting ripped to the ground by a Bayern player, but he nudged the ball to Messi, who took a touch and, with vision that Xavi and Iniesta would be proud of, slipped the ball through two Bayern defenders to Neymarwho sprinted past a hapless Mats Hummels before slotting past Neuer to make it 3-0.

“Chasing the away goal has cost Bayern dear,” mused Tyler. “Conclusive.”

Conclusive it was. Barcelona won the game 3-0, and even though they lost the second leg 3-2, a 5-3 aggregate triumph saw them into the semifinals where they dispatched Juventus 3-1 to win the trophy.

It’s been four years since Messi has played a home semifinal game in the Champions League, and if his last performance (and current supernova form) is any indicator, we could be in for a real treat at the Camp Nou on Wednesday evening.