The visitors, meanwhile, will miss out on the top two, but they are hoping to retain third place and qualify for the Copa Sudamericana.
Match preview
Olimpia failed to progress to the Copa Libertadores knockout rounds last season, but they have had no such trouble this time around, having secured their place in the top two with one game to spare.
Impressively, the Paraguayan side are one of three teams yet to lose in the group stage after picking up 11 points from their five matches (W3, D2).
With Diego Aguirre's side sitting one point above second-placed Atletico Nacional, they still have work to do if they are to wrap up top spot.
In their most recent outing, Olimpia eased to a 4-1 league victory over Resistencia, representing their third consecutive win in all competitions.
With Tuesday's fixture taking place at the Estadio Manuel Ferreira, the hosts can take confidence from the fact that they are unbeaten in eight Copa Libertadores home matches since losing 4-1 to Flamengo in August 2021.
Melgar are competing in the Copa Libertadores group stage for the first time since the 2018-19 campaign, and it has proven to be a difficult experience, with their five matches yielding four points.
After playing out a 1-1 draw in their opening game, Melgar went on to lose their next three group fixtures, leaving them without a win after four matches.
They managed to claim their first victory of the group stage on matchday five, as they cruised to a 5-0 home win over Argentina's Patronato.
While a place in the top two is out of reach, Melgar will drop down to the Copa Sudamericana if they can hold off fourth-placed Patronato, who are just one point behind.
The Peruvian side will head into Tuesday's contest in a rich vein of form after winning four and drawing one of their last five matches in all competitions.
Olimpia Copa Libertadores form:
D
W
D
W
W
Olimpia form (all competitions):
L
D
W
D
W
W
Melgar Copa Libertadores form:
D
L
L
L
W
Melgar form (all competitions):
L
D
L
L
L
W
Team News
The hosts are expected to be without the services of Saul Salcedo, Luis Caceres, Victor Salazar, Jhohan Romana, and Derlis Gonzalez due to injury issues.
Luis Zarate will continue his central defensive partnership with Mateo Gamarra, while Sergio Otalvaro and Facundo Zabala could operate at the two full-backs.
Having scored in three of his last four matches, Guillermo Paiva will be looking to continue his fine run of form when he leads the line on Tuesday.
As for the visitors, they are expected to start with a back three made up of Alec Deneumostier, Leonel Galeano and Jean Archimbaud.
Cristian Bordacahar returned to the starting lineup for the win over ADT Tarma, and he is expected to retain his place for Tuesday's contest.
Bernardo Cuesta, who has scored five goals in his previous three games, is set to feature in the front two alongside Tomas Martinez.
Olimpia possible starting lineup:
Olveira; Barreto, Zarate, Gamarra, Zabala; Cardozo, Silva, Gomez, Torres, Fernandez; Paiva
Melgar possible starting lineup:
Caceda; Deneumostier, Galeano, Archimbaud; Bordacahar, Tandazo, Cabrera, Orzan, D'Arrigo; Martinez, Cuesta
We say: Olimpia 2-1 Melgar
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