The hosts currently hold a one-goal lead after securing a 2-1 win at Estadio George Capwell last week, and if they are able to hold on to that lead, they will book their place in the next round against either Botafogo or Guarani.
Match preview
Defensa y Justicia were given an early scare in the first leg as they went behind in the opening five minutes of the match, but a late surge saw them overturn the deficit with Nicolas Fernandez and Gaston Togni both scoring in the final five minutes of regulation time to secure the victory.
With that result, the hosts have now registered at least one goal in each of their last six Copa Sudamericana matches this season and have only been shut out once, which was in their solitary loss in the group stage against Millonarios.
However, Julio Vaccari's side have not just been good in this competition but also made great strides in their domestic league, improving from 12th place in the second phase of last season to fifth in the first phase of this campaign.
They have also been formidable on their home patch, unbeaten in their last 12 matches with 10 wins and two draws while only conceding two losses in 19 matches at Estadio Juan Carmelo Zerillo in all competitions.
While they were marked as the outsider in last week's encounter, they managed to defy the odds with a win and are now the strong favourites to qualify for the next round, needing just a draw or better.
Meanwhile, despite taking the early lead in the last match against this opponent, Emelec were on the back foot for the majority of the 90 minutes, and it never really felt that they could hold on to their one-goal advantage throughout the match.
Hernan Torres's side were starved of possession for large periods and had to deal with wave after wave of attack by their opponents, who fired a total of 21 shots at goals with eight on target.
The first phase of the Liga Pro season saw them finish 13th in the league standings with just 14 points, and they also began the second phase on a poor note, drawing 0-0 to Libertad last weekend after being reduced to 10 men in the second half.
Adding to the unlikelihood of a turnaround in the match is their away record this season which reads as just one win in eight league matches on the road, along with two draws and five defeats.
Defensa y Justicia Copa Sudamericana form:
W
W
W
W
W
W
Defensa y Justicia form (all competitions):
Emelec Copa Sudamericana form:
D
D
W
W
D
L
Emelec form (all competitions):
Team News
Nazareno Colombo remains the only injury absentee for Vaccari, as the defender has not yet recovered from a knee injury he picked up against Centro Espanol a few weeks ago.
Fernandez's return to the starting 11 worked like a charm in the last match, and he should lead the line once again while Gabriel Alanis will be hoping to start this match, possibly in place of Santiago Solari, who was withdrawn just after the hour mark in the last match.
Joel Quintero and Jefferson Vernaza are the only reported absentees for the visitors, with both players still recovering from knee injuries.
Bryan Carabali had another excellent match for the visitors in the first leg, getting on the scoresheet for the second time in this competition, and will almost certainly start on the left flank with Romario Caicedo on the opposite end.
Defensa y Justicia possible starting lineup:
Bologna; Sant'Anna, Malatini, Cardona, Soto; Tripichio, Lopez, Barbona; Alanis, Fernandez, Togni
Emelec possible starting lineup:
Ortiz; Caicedo, Leon, Leguizamon; Carabali; Villalba, Agron, Garcia, Cevallos, Sosa; Angulo
We say: Defensa y Justicia 1-0 Emelec
The hosts were dominant in the first leg and were rarely troubled, aside from the early goal they conceded. They will likely look to get an early goal themselves in this one, which will put them firmly in the driver's seat, and we can see them sitting back thereafter and seeing out the match by shutting out their opponents.