This week we learned that Luka Modric's ethereal and seemingly infinite playmaking ability is as refined as it ever was at 35 years of age. 

We also saw Thomas Tuchel strengthen his stark reputation at Chelsea with an impressive 2-0 win over Atletico Madrid and watched another procession for Manchester City as they secured their place in the last eight of the Champions League.

Now that the dust has settled on European knockout football, it's time to turn our attention towards domestic action once again.

Ahead of the weekend, GIVEMESPORT has drawn upon data from our good friends at FotMob to identify five of the most captivating fixtures taking place across Europe this weekend. 

Here's where you should be focussing your attention: 

Celtic vs Rangers 

Competition: Scottish Premiership 

Kickoff: Sunday, 12:00 GMT

The unadulterated and historic hatred between Celtic and Rangers supporters makes the Old Firm derby one of the feistiest fixtures on the planet at the best of times. 

However, an intricate blend of circumstances has added a unique layer of significance to this particular encounter.  

Rangers were crowned SPFL champions on March 7 as Celtic were held to a 0-0 draw at Dundee United, and this is the first fixture for both sides since the title was confirmed.

When the two sides face off at Celtic Park on Sunday, the hosts will be expected to give the new champions a guard of honour to commemorate their achievement, one which deprived Celtic of their tenth consecutive title.

But Rangers opted against the traditional gesture of sportsmanship in 2019 when Steven Gerrard's side hosted Celtic at Ibrox after the Hoops had clinched their eighth title on the bounce.

That decision has understandably formed a key part of the narrative ahead of the Old Firm, with pundits and journalists debating whether Celtic should honour the new Scottish champions as they walk onto the field. 

Regardless of what happens pre-match, emotions will be running high and tempers will flare. 

It's got all the makings of the type of clash where form guides go out the window, and that can only make for an intriguing spectacle.

If there's one player you can bank on writing the headlines, it's Rangers' mercurial and infamously hot-headed talisman Alfredo Morelos. The Colombia international endured a slow start to the season but has scored seven goals in his last nine outings in the league. 

Celtic will need to get a grip of Morelos to stand any chance of restoring a sense of pride, but with a return of just one goal in their last three games they'll need to significantly improve at the other end of the field.

There is nothing but also everything to play for in Glasgow.

Lyon vs Paris Saint-Germain 

Competition: Ligue 1 

Kickoff: Sunday, 20:00 GMT

In light of the burglaries that took place at Angel Di Maria and Marquinhos' homes last weekend, drama taking place away from the field has dominated the news in the French capital in recent days.

Paris Saint-Germain managed to put that, and their surprising 2-1 home defeat against Nantes last weekend, behind them with a resounding 3-0 win over Lille in the Coupe de France last-16 on Wednesday evening.

With Lille currently leading the way in Ligue 1, PSG's comprehensive victory served as a timely warning to Lyon ahead of their weekend clash. 

Les Parisiens are level on points with Lyon but sneak ahead of their weekend opponents in the current Ligue 1 standings by virtue of goal difference. 

This is a classic title race six-pointer and one which Lyon will fancy their chances in having had nine days rest since their 1-1 draw with Stade Reims last time out. 

Lyon have won three of their five fixtures against PSG since moving to the Parc Olympique Lyonnais in January 2016, while they've only lost two of 14 home league games in the current campaign. 

However, Kylian Mbappe is beginning to find his groove under Mauricio Pochettino and comes into the game roaring with confidence after bagging a brace in midweek. 

When all is said and done at the end of the season, this is a fixture that both sides may look back on as a significant turning point.

Real Sociedad vs Barcelona 

Competition: La Liga 

Kickoff: Sunday, 20:00 GMT 

The newly-appointed Barcelona president Joan Laporta was inaugurated on Wednesday evening, and he will be watching with intrigue on Sunday as he begins to make preparations for the summer transfer window.

It's no coincidence that Lionel Messi's return to form has saved what appeared to be a stuttering season for Barcelona, putting them firmly in contention for the La Liga title with just nine games left to play.

The Argentine bagged a brace against Huesca on Monday evening to take his tally to 21 for the season in the league. 

Messi arrives in the Basque country on a stunning run of goal scoring form that has seen him notch 14 goals in his last ten league games, while he provided two assists in the only game on that run in which he failed to score.

That unrelenting streak will give Real Sociedad legitimate cause for concern, and the history books don't make for auspicious reading either.

Sociedad have only beaten Barcelona once in their last 15 fixtures across all competitions, with their only victory arriving in April 2016 courtesy of a header from Mikel Oyarzabal, who was just 18 years old at the time. 

Almost five years on, the prolific winger has established himself as arguably Sociedad's most deadly attacking outlet, scoring 12 and assisting eight in 32 games across all competitions this season. 

Barcelona's quest to usurp Atletico Madrid at the summit of La Liga is gathering pace but, if Sociedad do manage to end the Catalan outfit's 17-game unbeaten run in the league, then you can bet Oyarzabal will be the protagonist. 

Leicester City vs Manchester United 

Competition: FA Cup 

Kickoff: Sunday, 17:00 GMT 

Leicester City and Manchester United are engaged in a hotly-contested battle for second place in the Premier League but they take their domestic battle onto a new platform in the FA Cup this weekend. 

Both sides boast fine rosters of dynamic and pulsating attacking players, and their head-to-head record suggests there could be a goal fest at the King Power Stadium.

Since the Foxes returned to the Premier League in 2014, these two sides have scored 44 goals against one another in just 14 matches. 

The good news for Ole Gunnar Solskjaer is that United have only tasted defeat once, which arrived in the form of a 5-3 win for Leicester in their first clash against the Red Devils after returning to the top flight. 

David Nugent, Leonardo Ulloa and a certain Esteban Cambiasso were all on the scoresheet that day, while David de Gea, Luke Shaw and Juan Mata are the only survivors from Louis van Gaal's 18-man squad. 

United are unbeaten in their last ten domestic games and have kept clean sheets in seven of those fixtures, so the in-form Kelechi Iheanacho, who has scored five in his last three games, will need to be clinical alongside Jamie Vardy as their budding partnership continues to blossom.

Roma vs Napoli 

Competition: Serie A 

Kickoff: Sunday, 19:45 GMT

While Roma and Napoli are both well adrift of Inter Milan at the summit of Serie A, the Derby del Sole is a fixture that has seldom failed to entertain in recent years. 

The last nine league fixtures between these two historic teams have produced 31 goals in all, with Napoli winning five and drawing one. 

Paulo Foncesca welcomes Gennaro Gattuso to the Stadio Olimpico knowing that his side simply have to win to maintain their ambitions of qualifying for the Champions League this season. 

The teams are currently tied on 50 points and sit two points adrift of Atalanta in fourth place, but Napoli have a game in hand on their opponents this weekend and come into the match following a 1-0 win over AC Milan at the San Siro. 

Club captain Lorenzo Insigne has scored 13 and provided four assists in Serie A this season and, with the likes of Matteo Politano, Dries Mertens and Hirving Lozano all adding plenty of firepower to the Naples-based outfit, Foncesca will need a big defensive performance from his side to clinch a vital victory. 

As for the hosts, news earlier this week confirming that Henrikh Mkhitaryan, who has scored 11 and assisted as many across all competitions this season, will be absent for three to four weeks with a calf injury will be viewed as a major blow to their Champions League ambitions at a crucial stage in the campaign. 

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