Lionel Messi will renew acquaintances with Real Madrid on Tuesday night.
The Argentinean, who had spent his entire career at Barcelona until this season, spent well over a decade causing havoc for Los Blancos.
Across 45 games he bagged 26 goals and provided 14 assists as the Catalans largely dominated Spanish football.
He is now onto a new challenge in Paris and will be hoping to continue his impressive record against the La Liga giants.
PSG host Madrid at the Parc des Princes before heading to the Bernabeu three weeks later.
Messi has not produced the numbers we perhaps expected he would in France, but has enjoyed some of his finest moments for his new employers in the Champions League.
The Argentinean is chasing a fifth triumph in this competition whilst PSG are seeking their first.
Madrid, currently charging clear in La Liga, will provide stern opposition in the last-16 but Messi will be hoping to further add to his impressive history against Los Blancos.
We take a look at five of his finest moments against Barcelona's arch rivals.
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1) Hat-trick in 2007
The breakout game. Barcelona would surrender the title to Real Madrid, but this was the first glimpse into the future.
At just 19 Messi was showing signs of what was to come and ensured that Los Blancos didn't record a famous win at the Nou Camp.
Barcelona were continuously having to come from behind and the little Argentine levelled the scores for a third time in the 90th minute.
His quick touch left an opposition defender on the floor before he fired across Iker Casillas.
Messi received a huge from Ronaldinho, then the team's talisman, but it wouldn't take long for the teenager to assume his role.
2) Champions League semi-final, 2011
"He is just brilliant, best in the world bar none," hailed one commentator as Messi capped off a memorable night for his side at the home of their great rivals.
Barcelona travelled to the Bernabeu for the first-leg of the Champions League final. Jose Mourinho's Real Madrid knew they couldn't outplay the Catalans, but their physical approach backfired.
Pepe was sent-off, followed by the Special One. But whilst tempers flared Messi snuck in to put Barcelona ahead.
Then, in the dying stages, he received the ball off Sergio Busquets, rounds four players who try in vain to scythe him down before slotting past Casillas for what was one of the great Champions League goals.
He would complete the job a month later by scoring in the final win over Manchester United at Wembley.
3) Spanish Super Cup, 2011
It was a win that would only halt the changing of the guard but, at the time, it felt like a crucial moment.
Mourinho's Madrid were on the charge and the season's curtain raiser was a chance to hammer home a psychological blow..
The first-leg was 2-2 and it seemed destined for extra-time when it was the same scoreline at the Nou Camp.
Messi had already notched one on the night and then perfectly timed his run to make it 3-2, 5-4 on aggregate, with two minutes remaining.
The game is more remembered for the unsavoury scenes on the touchline as Mourinho clashed with Tito Vilanova.
Nevertheless, it is a contest in which Messi stood up to ensure, in that moment, Barcelona retained the upper hand.
4) Hat-trick in 2014
It didn't mean much ultimately as Barcelona lost the LaLiga title on the final day to Atletico Madrid.
But when they visited the Spanish capital in March it was very much a three-horse race and Los Blancos were looking to regain their crown.
In a seesaw game, that eventually finished 4-3, Barcelona took the lead and were forced to come from behind.
Messi would grab a treble, two penalties after a neat finish in the first-half. His second spot kick would prove to be the winner as he slotted home with six minutes left.
The Catalans finished the season with no major trophy, but hat-tricks by a visiting player at the Bernabeu are a rarity, with only three recorded by away players in the last 30 years.
5) Bernabeu winner, 2017
Arguably the Argentine's finest moment followed perhaps his most iconic image.
Two minutes of stoppage time was about to expire with the score at 2-2 and Barcelona on the break seeking to close the gap at the top of the table.
Jordi Alba cut the ball back for Messi who, from the edge of the area, slotted past Keylor Navas in the Madrid goal.
"He is superhuman," claimed the commentator as Messi took his shirt off before holding it up to the Bernabeu crowd, now stunned into silence.
It is easy to forget that Barcelona's efforts didn't stop Los Blancos winning the title as they record the double that year.
Yet Messi's strike, his 500th goal for the Catalan club, is the moment that will arguably age greater than any other.
