An encounter of huge magnitude, between two of the most recognised clubs in world football, sees Barcelona and Manchester United go head-to-head in the UEFA Europa League last-16 play-off.
The Red Devils and La Blaugrana need no introduction to one another. In years gone by they have shared a pitch on a fair few grand occasions. The two heavyweights have previously met 10 times in the Champions League and they contested two UCL finals in 2009 and 2011, as well as a semi-final tie in 2008.
Since their remarkable capture of European glory against Bayern Munich at Camp Nou in 1999, United have failed to score in their two matches at Barcelona's iconic stadium. which has a capacity nearing 100,000.
The most recent (competitive) meeting between Barca and United came in the 2018/19 season, as Lionel Messi inspired his team to a 4-0 aggregate win over Ole Gunnar Solskjaer's men in the Champions League quarter-finals.
With both clubs now undergoing respective transition periods, they find themselves bound to lock horns in Europe's secondary club competition.
For the first time ever, these teams are due to meet in a European knockout competition outside of the Champions League. This two-legged play-off essentially serves as the Europa League Round of 32, with the eight group winners already in the hat for the last-16.
For the second year running, Barca finished third in their Champions League group and thus were demoted to the Europa League. United, meanwhile, ended runners-up to Real Sociedad in their UEL group.
Notwithstanding the tie being in the Europa League, this fixture still pits together two of Europe's biggest clubs and most in-form teams.
Both have the credibility to be Champions League finalists, yet one of them will be knocked out of Europe next week.
Barcelona legend Xavi has intentions of returning his club to their glory years. Ahead of this massive fixture his men are unbeaten in their last 16 matches across all competitions, winning all but one of those and keeping nine clean sheets in the process.
Domestically, Barca hold an 8-point lead over rivals Real Madrid.
Xavi was on the winning side as Pep Guardiola outsmarted Sir Alex Ferguson in the 2009 and 2011 Champions League finals, though this will be a maiden managerial duel with the Red Devils for the 43-year-old.
Xavi's side were last on the losing side in October, against Bayern Munich, and Erik ten Hag will be eager to inflict defeat on his opposite number.
Just as Xavi hasn't faced United as a coach, so too Ten Hag has never come up against Barcelona in a managerial capacity.
Barca would still undoubtedly be close to Ten Hag's heart, as two of his managerial influences, Johan Cruyff and Louis van Gaal both managed the Catalan club during the 1990s.
United's most obvious goalscoring threat comes in the form of Marcus Rashford. The 25-year-old has netted 13 goals in 15 matches since the World Cup, taking his tally to 21 goals for the season.
Rashford is beaming under Ten Hag's system and the England forward is one shy of matching his best goal returns in a single season (22 goals in 44 matches, 2019/20).
Rashford's progress this term gives partial insight to the work being put in behind the scenes and he, more than anyone else, is reaping the rewards of the collective efforts at Carrington.
It is no coincidence that Rashford's upturn in confidence and form has come following the appointment of Benni McCarthy to Ten Hag's coaching team.
Following McCarthy's arrival, Ten Hag suggested that a striker coach was just as imperative as a goalkeeping coach or any other specialist trainer.
An ex-Premier League striker and South Africa international, McCarthy landed a gig in Manchester last summer and his expertise have so far proven influential to United's attacking players.
At the other end of the pitch, David de Gea reached 400 games in the Premier League as United won 2-0 win against Leeds Utd at Elland Road last time out.
De Gea, 31, became the youngest goalkeeper to reach this landmark and just the ninth player to do so with a single Premier League club. He is also the first United keeper and the first non-British player to rack up 400 outings in the Premier League era.
Only two ex-United players, Ryan Giggs (632) and Paul Scholes (499) have more PL appearances than De Gea.
In addition, the Spaniard has equalled Peter Schmeichel's record of 178 clean sheets for the Red Devils. De Gea sits fifth in Premier League history for the most clean sheets and his tally of 139 shutouts is twelve short of Mark Schwarzer in third place on that particular list.
Ten Hag has added three faces to his Europa League squad for the rest of the season, with all of his January signings set to contribute to the Red Devils' bid for European silverware.
Wout Weghorst, Marcel Sabitzer and Jack Butland all joined United on loan last month and the trio have filled in the vacant spots in the set-up.
Cristiano Ronaldo (Al-Nassr) and Axel Tuanzebe (Stoke City - loan) left Old Trafford mid-season while goalkeeper Martin Dubravka was recalled by parent club Newcastle Utd.
Lisandro Martínez is unavailable through suspension after accumulating three yellow cards in the group stage. Sabitzer is also suspended for the first leg at Camp Nou, after the Austrian midfielder picked up three bookings with Bayern in the Champions League.
Anthony Martial, Scott McTominay and Antony are all nursing injuries.
Fortunately for United, they will be able to count on Casemiro who is serving a three-match domestic ban following a red card against Crystal Palace earlier this month.
Available for this European tie, Casemiro is most familiar with Barcelona having played more against the Catalans than any other club throughout his senior career.
Should the Brazilian feature at Camp Nou, it would be his 20th meeting with La Blaugrana. Only this time, the five-time Champions League winner will be donning the white of Manchester United rather than Real Madrid.
Within Xavi's ranks, the spotlight may be on a certain Frenkie de Jong after the Barca midfielder was heavily linked with a move to United last summer.
De Jong, 25, was reportedly Ten Hag's primary transfer target having known one another from their time together in Amsterdam, however the player was reluctant to leave Barcelona.
An Ajax academy graduate, De Jong starred in the 2018/19 season as Ten Hag's team came agonisingly close to reaching the Champions League final.
Overcoming Barcelona over two legs may cause De Jong to reconsider being part of Ten Hag's well-oiled machine in Manchester.
Sergio Busquets, an ingredient of Barcelona's in the 2009 and 2011 Champions League finals against United, is set to miss this bout with an ankle injury. La Blaugrana have another significant absentee in Ousmane Dembele, the France international ruled out with a thigh problem.
Kick-off comes live from Camp Nou at 17:45 GMT.
The return leg takes place next week Thursday, at Old Trafford, at 20:00 GMT.