On Tuesday night, Ole Gunnar Solskjaer will return to the ground that arguably defined his career as a player at Manchester United, as the Camp Nou set the scene in 1999, and will proceed in doing so this week.
This time around, though, Solskjaer will be in the managerial seat of the side that achieved success on that famous night against Bayern Munich.
United enter this week's fixture as heavy underdogs, considering the current state of the opposition, the venue, and the fact that Erneste Valverde's team sustained a 1-0 lead in the first leg at Old Trafford.
The comeback required is reminiscent of what was needed 20 years ago, but will Solskjaer again be able to manufacture the goods?
In order to do so, the task will be made considerably more realistic if United are somehow able to nullify Barcelona's attack. This is obviously easier said than done, but it's plausible when taking into account how the first leg unfolded. The narrative surrounded Lionel Messi and how special efforts should be made in order to prevent his quality from impacting the match.
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The problem, though, was even despite Messi's relative below-par performance, Barcelona still managed to score largely because of their second-best attacker, Luis Suarez. The Uruguayan striker has a history with United, and he demonstrated that when celebrating.
How then, are United able to ensure that Suarez is kept quiet alongside Messi? The answer, somewhat surprisingly, is by employing largely the same tactical approach, certainly in terms of some aspects.
There are numerous downsides to facing players such as Messi and Suarez, and very, very few positives. One of those positives, though, is that they aren't the quickest. Suarez is now 32 years old, and although he's not particularly slow, he's not an intimidating threat when affording space in behind.
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This is what influenced the defensive assurance that United displayed on the night, as an ambitiously high line was deployed which allowed United to remain compact from back to front, shown below.
This then restricted the space that Messi was able to play in, which consequently cuts off a lot of the supply to Suarez. Often, this isn't an issue for Barcelona due to their usage of Jordi Alba, who unlike Suarez and Messi, could certainly be considered as fast and threatening when allowed space.
Valverde largely opted against deploying Alba in advanced areas, though, with view to him remaining cautious to prevent United from counter-attacking through the likes of Marcus Rashford. As a result, the second leg may be a case of stick or twist in regard. Will Valverde allow Alba to advance, but concede space for Rashford, or will he play safe with Alba to ensure United's threat is nullified?
It's impossible to predict at this stage, but the better and more efficiently United attack, the more reserved Alba will become, and this will have a ripple effect related to how United can then be compact around the likes of Suarez and Messi, with an example pictured below.
Ultimately, the tactical aspects appear finely balanced, but United can certainly play on the general lack of pace in Barcelona's attack.
The way in which Barcelona adapt to such a problem largely involves Alba, but if he moves forward, Rashford can cause problems on the break.
Overall, despite the result, United didn't do a lot wrong in the first leg, and if they perform similarly, then Barcelona's attackers may be frustrated once more.
