Real Madrid have rolled into town.
The Spaniards, in case you didn't know, have an affinity with Glasgow.
Twice before Los Blancos have clinched the European Cup or Champions League at Hampden - 1960 and 2002.
It does not get any better or more glamorous for Celtic than this.
A Champions League group stage opener against the defending European champions under the disco lights at Parkhead.
The Glasgow Derby could not have gone any better with Ange Postecoglou's men dishing out a 4-0 drubbing to Rangers to move points clear in the Scottish Premiership title race.
Can Celtic stun Los Blancos and pull off mission impossible against Carlo Ancelotti's men?
They did it at Parkhead in 1980 in the European Cup quarter-final first leg.
Can history repeat itself? Who will Postecoglou pick in the attempt to do so?
Our writers have their say...
Sean Martin
How can you drop someone after a two-goal derby display? I prefer to think of it not as 'dropping' Liel Abada but just as rotating him out with the game in front of Celtic in mind.
Daizen Maeda's pressing qualities could be the difference on the Champions League stage and - whether on the left as usual or the right as he has appeared a couple of times recently - I think his presence is required.
The rest of the team will stay as-is save for the inclusion of Moritz Jenz at left centre-back instead of Carl Starfelt after the Swede's knee injury against Rangers.
Kyogo Furuhashi, who appeared at training on Monday despite being forced off with a shoulder knock after four minutes on Sunday, will resume his place as the attacking focal point.
Sean's team: Hart; Juranovic, Carter-Vickers, Jenz, Taylor; McGregor, Hatate, O'Riley; Jota, Kyogo, Maeda
Tony Haggerty
Celtic's 4-0 hammering of Rangers was all the evidence that was required to convince Ange Postecoglou and his players that their attacking style can yield success certainly at the domestic level.
In Europe, it may well be a different story.
This is why there will be a slight tinkering with the side for this match against the La Liga giants.
Joe Hart will start in goal alongside three of the tried and tested back four - Josip Juranovic, Cameron Carter-Vickers and Greg Taylor. That leaves one place up for grabs and Moritz Jenz will occupy that role at the expense of Carl Starfelt.
The midfield triumvirate will stay unchanged as Callum McGregor, Matt O'Riley and Reo Hatate get set to attack the Spaniards with gusto.
In attack, the red-hot Liel Abada will retain his place after his two-goal salvo and dominant display against Rangers.
That means Daizen Maeda will lose out as will his fellow countryman Kyogo Furuhashi, who despite training may not be risked from the start because of the shoulder injury sustained against Rangers.
The untouchable Jota and Giorgos Giakoumakis will form the front three hoping to cause problems for Los Blancos.
Tony's team: Hart; Juranovic, Carter-Vickers, Jenz, Taylor; McGregor, Hatate, O'Riley; Jota, Giakoumakis, Abada
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