The visitors, meanwhile, could still progress to the knockout stages with a win, but they would require a favour from Aucas against Flamengo.
Match preview
Despite falling to a 2-1 defeat to Flamengo in their last match in this competition, Racing saw their progression to the last-16 confirmed with a game to spare after Nublense and Aucas drew against each other.
As such, there is little pressure on their shoulders ahead of their final group game at Estadio Presidente Peron on Thursday, although they will want to end the first stage in style by securing first position.
Fernando Gago, who made 61 caps for Argentina before his retirement in 2020, has managed the club since October 2021, and he was a whisker away from winning the title in his first season in charge. Ultimately Jonathan Galvan's missed penalty against River Plate saw them finish second on the final day.
This time around, El Primer Grande find themselves occupying a mid-table position after playing 21 league games, with runaway leaders River looking uncatchable for any other team.
Gago will therefore be hoping for a deep run in South America's primary continental competition in order to ensure this campaign is remembered as another successful one.
Nublense, meanwhile, are already punching above their weight to find themselves in the group stage of the Copa Libertadores, having only ever appeared in the Copa Sudamericana until now.
Should they finish above Aucas and hold onto third spot in the group, Jaime Garcia's side would drop down into South America's secondary tournament, with their hopes of remaining in the Copa Libertadores hanging on by a thread ahead of their trip to Avellaneda.
The Chilean Campeonato Nacional runners-up, who were only promoted from the second tier three years ago, must beat Racing on Thursday while hoping that Aucas defeat Flamengo. With their goal difference currently five goals inferior to Flamengo, there would also need to be a considerable swing.
With Diablos Rojos currently lying 12th in their domestic table after 15 matches, albeit only 10 points off the summit in an incredibly tight division, this could represent their last chance for some time in terms of dining at South America's top table.
Racing Club Copa Libertadores form:
W
W
D
W
L
Racing Club form (all competitions):
D
W
L
D
W
D
Nublense Copa Libertadores form:
L
L
W
D
D
Team News
Racing appear set to be without Nicolas Reniero, Leonardo Sigali, Emiliano Vecchio, Leonel Miranda and Johan Carbonero due to injury.
With their progression to the last-16 already wrapped up, Gago could hand the likes of Matias Tagliamonte, Maximiliano Moralez and Baltasar Gallego Rodriguez a chance to impress him from the start.
Nublense, meanwhile, will be without Rafael Caroca through suspension after an accumulation of yellow cards, with Lucas Abascia likely to replace him at the heart of the visitors' defence.
Nicolas Zalazar will also miss out after being sent off during his side's 0-0 draw against Aucas, leaving Garcia with plenty of solutions to solve at the back.
Racing Club possible starting lineup:
Tagliamonte; Mura, Aviles, Piovi, Rojas; Nardoni, Moreno, Oroz; Moralez, Romero, Rodriguez
Nublense possible starting lineup:
Perez; Cerez, Abascia, Guerrero; Rebolledo, Leiva, Reyes, Zuniga, Campusano; Munoz, Rubio
We say: Racing Club 1-1 Nublense
With Racing likely to rest a few key players given their disappointing position in Argentina's Primera Division, we believe Nublense have a chance of pulling off an upset on Thursday.
However, they may fall just short of grabbing the win which they require in the end, although in truth even that would be unlikely to take them through to the knockout stages in any case.