Guillermo Barros Schelotto's men defeated Brazil's Ponte Preta 3-1 on aggregate to win the title in December with Victor Ayala and Ismael Blanco scoring in a 2-0 home win, which sealed the silverware for the Argentine club.
The club from the province of Buenos Aires have played in the Copa Libertadores four other times since their first qualification in 2003 but need to win a two-legged play-off against Caracas to reach the group stage - or second round - this year.
Lanus will head to the Venezuelan capital on Thursday having not played a competitive fixture since December 16 when they drew 2-2 away to Newell's Old Boys in the final round of the Argentine Primera Division's Torneo Inicial.
In contrast, Caracas have resumed league action in the Venezuelan Primera Division with three games since January 12.
Caracas sit fifth on the league table in Venezuela after a win and two draws.
Bolivia's Oriente Petrolero and Nacional of Uruguay will get the first stage of the Copa Libertadores underway on Tuesday.
The Bolivians will host Nacional having won just one of their past five games, although the visitors have yet to resume competitive action this year.
Mexican club Morelia will take on Santa Fe of Colombia, while on Wednesday, Sporting Cristal of Peru host Brazil's Atletico Paranaense and Botafogo travel to Ecuador to play Deportivo Quito.
Botafogo finished fourth in the Brazilian Serie A last season to reach the Copa Libertadores' first round.
The Rio de Janeiro-based club will be without Clarence Seedorf after the Dutch midfielder returned to Europe to become Milan's head coach but should be confident with the likes of Rafael Marques, Elias and Nicolas Lodeiro involved against Quito.
In the other first round first leg, Universidad de Chile will welcome Guarani of Paraguay to Santiago on Thursday.
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