Group B remains wide open, with all four sides still in with a chance of progressing to the knockout stages, although Olimpia are currently three points behind Tachira, who also have a far superior goal difference.
Match preview
Olimpia were dealt a blow in their quest to qualify for the knockout stages when they narrowly lost 1-0 at home to Internacional last Friday.
The Paraguayans were on the backfoot for the majority of the game and they were thankful goalkeeper Alfredo Aguilar made several saves to keep the scores level.
Olimpia's task got tougher when Saul Salcedo was sent off midway through the second half, and that dismissal proved costly as Internacional managed to break the deadlock seven minutes from time when Yuri Alberto fired his effort into the bottom right corner. Alberto was then given his marching orders in stoppage time but the visitors held on to claim all three points.
Sergio Orteman's side improved from their 6-1 thrashing in the reverse fixture with Internacional earlier this month, but another defeat means that they sit bottom of Group B heading into the final match.
El Decano have failed to progress from the group stages of the Copa Libertadores in each of the last two seasons, but there is still an outside chance that they can qualify for the next round. They will, however, need to beat Deportivo Tachira by a four-goal margin and hope that Always Ready lose to Internacional.
Olimpia were beaten 3-2 against Tachira in their opening group game but Orteman will be hoping that his side have learnt from that encounter and give an improved performance on Wednesday.
Deportivo Tachira claimed their third successive home win of the group stages in style when they beat Always Ready 7-2 last Thursday.
The Aurinegro raced into a 4-0 lead before half time, thanks to strikes from Freddy Gondola, Maurice Cova, Yerson Chacon and Lucas Gomez. Gondola scored his second of the game and Tachira's fifth just seconds after the break, before goals from Michael Covea and Douglar Martinez capped a brilliant victory for Juan Tolisano's side.
Tachira are now level with Group B leaders Internacional with nine points, three clear of Always Ready and Wednesday's opponents Olimpia.
As well as impressing in the Copa Libertadores, the Aurinegro have begun their league campaign brightly and are currently sitting top of the Venezuelan Primera Division after winning four of their first five matches. They were, however, beaten in their most recent league encounter on Saturday, losing 2-1 away at Zamora FC.
Securing all three points for Tachira in Paraguay will see Tolisano's men progress to the knockout stages for the fifth successive season.
Olimpia Copa Libertadores form:
Olimpia form (all competitions):
Deportivo Tachira Copa Libertadores form:
Deportivo Tachira form (all competitions):
Team News
Olimpia centre-back Salcedo is suspended for their final group game, which will likely see Antolin Alcarez start in his place alongside Luis Caceres.
Full-back Robert Ergas continues to recover from a cruciate ligament injury and will not be available for Thursday's game.
Wingers Alejandro Silva and Nestor Camacho, who began on the bench against Internacional, could be handed starts on Wednesday at the expense of Hugo Escobar and Marcelo Estigarribia
As for Deportivo Tachira, 39-year-old striker Edgar Perez Greco has now recovered from injury and will be in contention to start against Olimpia, although both Covea and Gomez are expected to lead the line once again.
Left-back Jose Granados has been favoured in the Copa Libertadores so far and is expected to keep his place in the first XI ahead of youngster Naicol Contreras, who has impressed during their domestic campaign.
Olimpia possible starting lineup:
Aguilar; Otalvaro, Caceres, Alcarez, I. Torres; Ortiz, Rojas; Silva, Recalde, Camacho; W. Gonzalez
Deportivo Tachira possible starting lineup:
Varela; Hernandez, Vivas, Trejo, Granados; Flores; Chacon, Cova, Gondola; Covea, Gomez
We say: Olimpia 1-2 Deportivo Tachira
Deportivo Tachira have conceded 11 goals from their five Group B games, which will encourage Olimpia, who need to win by a four-goal margin to boost their hopes of progressing to the knockout stages. The hosts, however, have also looked vulnerable defensively, conceding 12 times from their five matches.
Goals are to be expected on Wednesday evening and we feel that the visitors have enough to secure all three points once again against the Paraguayans, to book their place into the last 16.