The latest chapter of arguably football's greatest rivalry will be written in the early hours of Wednesday morning when River Plate welcome Boca Juniors to the Estadio Monumental for the first leg of their Copa Libertadores semi-final.
The Buenos Aires rivals met in the final of the competition for the first time last season in an encounter which was quickly written into infamy due to an attack on the Boca Juniors bus which eventually forced the second leg to be played in Madrid.
As if there was not already enough animosity between these two sides, the events of last year only cranked up the hatred the bitter rivals have for each other.
What was dubbed "The Superfinal", "The final to end all finals" and the biggest occasion in Argentine sporting history ultimately proved to be one of the most shameful and embarrassing occasions for the country.
It was bad enough that the first leg was postponed less than two hours before kickoff due to a waterlogged pitch, but the scenes which preceded the second leg cast a dark cloud over Argentinian football.
An attack on the Boca Juniors team bus en route to the match left players injured as a result of broken glass and pepper spray, eventually leading to the game being postponed again and played more than 10,000 kilometres away in Madrid.
River Plate ultimately gained eternal bragging rights with a 5-3 aggregate victory in the first Copa Libertadores Superclasico final, but the game was not played until almost a month after the first leg and ultimately their fourth continental crown was overshadowed.
For the two sides to meet again in the semi-finals of this competition is a major occasion, then, with a match against either Gremio or Flamengo awaiting them in the first one-legged final at the Estadio Nacional in Santiago, Chile.
River and Boca have met since those dark events of 2018, doing so as recently as September 1 when the two sides played out a tense stalemate at the Monumental - thankfully a much lower-key affair than their previous showdown.
It is Boca who have fared the better domestically so far this season, leading the way in the Argentine Superliga having won five and drawn three of their eight games so far, leaving them two points clear at the top and four above River Plate.
Most impressive has been their defensive record, though; Sunday's 1-1 draw with Newell's Old Boys saw them concede for the first time in the league all season, having kept clean sheets in all seven of their opening matches.
The clean sheet against River Plate at the Monumental was the most valuable of those, particularly considering Marcelo Gallardo's side have scored a league-high 17 goals this term.
Wednesday's hosts have already been beaten twice in the league this season, though, and are winless in their last three home games, picking up just one point and scoring only one goal in that time.
However, when it comes to the Copa Libertadores River are unbeaten in 13 matches and have lost just one of their last 24, whereas Boca have tasted defeat in this season's competition already.
River Plate form: DDWWLW
Boca Juniors form: WDDWWD
Both of these sides took the weekend to rest a number of their star names, but they will restore themselves to full strength for this showdown.
River Plate possible starting lineup:
Armani; Montiel, Martinez, Diaz, Casco; Perez, Fernandez, Palacios, De La Cruz; Suarez, Borre
Boca Juniors possible starting lineup:
Andrada; Weigandt, Lopez, Izquierdoz, Mas; Marcone, Capaldo, Soldano, De Rossi, Mac Allister; Hurtado
We say: River Plate 1-1 Boca Juniors
First legs of semi-finals are often nervy affairs, and with so much riding on this match it is unlikely to be any different. Boca do not concede many goals and will be happy to come away from the home of their great rivals - and the defending champions - with a draw.