After knocking Real Madrid out of the Champions League last season, holders Chelsea will be hoping to repeat that trick in the quarter-finals this term.
These two teams locked horns in the semi-finals in the previous campaign and it was the Blues who came out on top 3-1 on aggregate - drawing the first leg 1-1 in Spain before triumphing 2-0 in West London.
It was a brilliant performance from Chelsea, but the circumstances in which they went into the first leg of that last-four clash last season are very different to how they head into Wednesday's contest, with the Blues 12/1 to retain their European crown.
Before the semi-final encounter, the Premier League outfit were on a three-game unbeaten run and hadn't conceded a single goal during that period, but they go into the first leg of the quarter-final against Los Blancos off the back of a 4-1 thumping at the hands of Brentford.
Having gone 1-0 ahead at Stamford Bridge, you can be excused for thinking the Blues would put their foot down and hammer home their advantage, but this turned out not to be the case as the Bees - inspired by Denmark international Christian Eriksen - scored four goals without reply to pull off a stunning victory.
In the aftermath of that defeat, Thomas Tuchel insisted nothing special is required to turn that form around ahead of Wednesday's European tie, but is he right to say this?
It's worth noting that Tuchel's managerial record against Ancelotti is good, with the German tactician winning three and drawing two of the seven meetings with the Italian maestro.
Based on that evidence, it's fair to say the Chelsea boss has produced managerial masterclasses against a head coach who is so revered for his ability to get the job done in the key games.
Ancelotti is also under pressure after the recent 4-0 El Clasico defeat to Barcelona, a result which stunned the league leaders and kept the Catalans' slim title hopes alive.
A draw in the first leg at Stamford Bridge on Wednesday is priced at 12/5, while the Blues are 13/5 to edge a victory by a one-goal margin and a 1-1 draw is available at 11/2.
Of course, it would be foolish to think Madrid won't get the better of Chelsea across the two legs given the Spanish club's illustrious history in Europe.
Los Blancos have won a record 13 European Cups, the last of those coming in 2018 when they lifted the trophy for the third straight year, so they are more than capable of pulling off big results when needed.
Ancelotti's men also bounced back from the loss to Barcelona with a 2-1 win at Celta Vigo, a result which extended their winning away run in La Liga to three matches, and they have a forward in sparkling form leading the line.
France international Karim Benzema netted both goals in that victory, taking his league tally to 24 goals, as he leads the division's scoring charts, but he has also been thriving in Europe.
The 34-year-old has scored eight times in the Champions League this term, leaving him third in the scoring charts, and he can be backed at 7/4 to score at any time on Wednesday.
It could turn out to be quite a tactical, cagey affair in the first leg, therefore it could be worth backing under 2.5 total goals at 8/11 as neither side wants to put themselves out of the tie before the return fixture at the Santiago Bernabeu.
In Wednesday's other Champions League quarter-final, first leg, Villarreal - who knocked out Juventus 4-1 on aggregate in the last-16 - play host to Bayern Munich.
There is no denying how fantastic this run has been for the Yellow Submarine, but their quest for glory could be stopped dead in its tracks by the formidable Bavarians.
Julian Nagelsmann's men have a nine-point gap at the top of the Bundesliga, so they have been able to put lots of focus on the Champions League recently, and they head to Spain on an eight-game unbeaten run across all competitions.
Bayern have scored 23 goals during this purple patch and they have once again been indebted to Robert Lewandowski, who has 31 league goals for the season and also leads the Champions League charts with 12 strikes.
The German giants can be backed at 11/20 to win the first leg, are 11/4 to triumph by a one-goal margin and are 1/12 to progress to the semi-finals.
While Bayern are expected to get through this tie, you can never write off a team in Europe that is managed by Unai Emery, who has such an affinity for the big stage.
The former Arsenal boss is a four-time Europa League winner, having led Sevilla to three straight titles before claiming the spoils with Villarreal last season.
He also came close with the Gunners, who finished asrunners-up in 2018/19, and he will be hoping to notch the first Champions League trophy of his managerial career.
Emery has defied expectations time and time again and he will be looking to use all of his experience against Nagelsmann, who is still the young kid on the block at 34 years of age.