The Italian coach has now led Los Blancos on a 26-match unbeaten run that is only bettered by the team trained by Leo Beenhakker (34 games without defeat) in 1988-89
All at sea and lacking balance in the early months of the season, as Ancelotti admitted frequently, Madrid lost 1-0 to Atletico in a derby clash at the Santiago Bernabeu in late September. Then Madrid went down to its fiercest foe, Barcelona, in a 2-1 defeat at Camp Nou a little less than a month later.
Since then, however, Madrid's record is unblemished: 21 wins, four draws and no defeats. Victories against Sevilla, Rayo Vallecano, Real Sociedad, Almeria, Galatasaray, Valladolid, Olimpic Xativa, FC Copenhagen, Valencia, Osasuna (over two legs in the Copa del Rey), Celta Vigo, Espanyol (once in La Liga and twice in Copa) Betis, Granada, Atletico (home and away in the cup), Villarreal, Getafe and now Elche have all been obtained by the capital club, along with draws at Olimpic, Juventus, Osasuna and Athletic Bilbao.
The record was already more impressive than Fabio Capello's Madrid side of 1996-97, which managed 25 games unbeaten but drew eight of those in the first spell of the team's only other Italian coach.
That run was brought to an end by Celta as the Galicians claimed a 2-0 victory in La Liga. And four days later, Beenhakker's side suffered what is still one of the club's worst-ever European defeats - a 5-0 loss away to Arrigo Sacchi's era-defining AC Milan team. Ancelotti opened the scoring in that game, incidentally, with a stunning strike from outside the box after dribbling past two Madrid players.
Despite that disappointment, the Dutchman led Madrid to La Liga and the Copa del Rey that season, while Capello's 1996-97 team also claimed the Primera Division title - an impressive feat considering Madrid had only managed to finish sixth in the previous campaign.
That team saw its unbeaten run ended by Barcelona in a 3-2 defeat to Bobby Robson's side in the Copa del Rey in the Catalan capital.
Madrid's last loss came at Camp Nou as well, but the next Clasico meeting is not until March 23 in La Liga and will be played at the Bernabeu, with the two teams to lock horns once again on April 16 in the final of the Copa del Rey at Mestalla.
"We have to take care [of the players]," Ancelotti said on Friday. "Physically, I don't think we will have a problem but there are lots of games coming up - and lots of important ones."
And he added: "The players know that this is a moment in which all of the games are important - and they are focused only on Saturday."
To keep the run going towards a new record, Madrid will need to avoid defeat against Atletico at the Vicente Calderon next weekend, as well as progressing through the last 16 of the Champions League without losing either leg to Schalke and repeating the feat in the quarterfinals of the continental competition.
Intriguingly, the league game against Barca at the Bernabeu would then be Madrid's 34th in this sequence if it can make it that far. The Blancos would need to emerge unscathed from that test plus the Primera Division fixture at Valladolid days later as well in order to set a new all-time record of 35 matches without defeat in all competitions.
Barca's best run, incidentally, is 28 games unbeaten in 2010-11, when the Catalan club claimed La Liga and the Champions League as well as reaching the final of the Copa del Rey under Pep Guardiola. That side saw its streak end with a 3-1 cup defeat at Betis in January, having won the first leg 5-0 at Camp Nou.
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