A year and a day later, both sides are in action again in the competition on Tuesday -- this time at a much earlier stage. The coronavirus pandemic has pushed things back. The final of the 2020 Libertadores will in fact take place at the end of January 2021. And the knockout phase, featuring the 16 surviving teams from the group stage, gets going this week.
Only twice in the last 15 years has the title gone outside Brazil and Argentina. Last year, of course, featured a final between clubs from the continent's big two. They dominate the last 16, with Brazil supplying six clubs and Argentina three. But this year the battle between them could be resolved earlier. All three Argentine sides are up against Brazilian opposition.
River Plate will be considered the favourites to get past Athletico Paranaense. With no competitive games behind them, River showed some excellent form when the Libertadores resumed in mid September, with young striker Julian Alvarez especially impressive. And with domestic football in Argentina now up and running, River should have shaken off any remaining ring rustiness.
But Athletico, who had been struggling in the Brazilian league, have suddenly found some form, and go into Tuesday's game on the back of four consecutive wins. And in the first leg they also have the advantage of the artificial pitch in their stadium in Coritiba. Their problem -- and this is a theme in this week's matches -- is that they have a number of players out of action with COVID-19.
Racing of Argentina are on a run of four consecutive defeats and they are also in turmoil inside the club, with director of football Diego Milito about to stand down. All of this emphasises the reason Flamengo are favourites, the defending champions who are second in the Brazilian league, level on points with leaders Atletico Mineiro. Flamengo are not at full strength, though, and new coach Rogerio Ceni is still finding his feet, but even so they have an exciting array of attacking options. The defence, though, has been a problem all year and it is this which makes the tie with Racing so full of potential. Racing coach Sebastian Beccacece favours a high tempo, attacking game, and it will be interesting to see how many risks he is prepared to run in a quest to probe the Flamengo back line, especially on home ground in the first leg.
There is no clear favourite in the third Brazil vs. Argentina clash, Wednesday's meeting between Internacional and Boca Juniors. The recent loss of coach Eduardo Coudet, who accepted a job in Spain with Celta Vigo, is a blow to Inter that may tip the balance Boca's way. But the Argentines are waiting anxiously on the fitness of winger Eduardo Salvio, who was in top form before the break for FIFA dates.
There are two clashes between teams from Brazil and Ecuador. Santos face the tougher task against 2008 champions LDU, or Liga of Quito, not least because of the altitude of the Ecuadorian capital, where Tuesday's first leg will be played. The form of Santos in the group phase -- five wins and a draw -- was a triumph over adversity. The club has financial and administrative problems -- the president has just been impeached -- and now some players have gone down with COVID. Literally and metaphorically, then, Santos have a mountain to climb.
Palmeiras, meanwhile, are strong favourites against little Delfin, even though the Brazilians are having to deal with an outbreak of COVID in their ranks, as well.
Indeed, last week's COVID epidemic inside the Uruguay national team could have started from Palmeiras left-back Matias Vina. It spread to Uruguayan club Nacional, who will be missing two of their best players for the trip to the third side from Ecuador, the highly impressive Independiente del Valle.
The other Brazilian team, 2017 champions Gremio, are away on Thursday to Guarani of Paraguay, who have been the best of this year's surprise sides. At best, the fourth-biggest club in their country, Guarani, had to fight their way through all of the qualifying rounds merely to reach the group stage, eliminating Brazilian giants Corinthians on the way. Well coached by Gustavo Costas, they have assembled an interesting squad. Gremio, though, will be seen as the favourites, not least because their domestic form has picked up admirably in the last couple of weeks.
And the round is completed with the meeting of Paraguay's Libertad and Jorge Wilstermann of Bolivia. There are 10 former champions in the last 16. This clash ensures that at least one of the last eight will be seeking to win the trophy for the first time, dreaming of performing a lap of honour like the one of Flamengo on Nov. 23, 2019.