Ruben Israel's side took a promising lead ahead of the return match next Wednesday, with Miguel Samudio opening the scoring with a 37th minute free-kick before Brian Montenegro added a second in first-half injury time.
However, Samudio is adamant the tie is not over yet.
"The result is quite good," he told Fox Sports. "We know how important a home win was but we cannot be satisfied with this."
Itagui of Colombia beat Uruguay's River Plate 1-0 at home with Victor Cortes scoring the winner 18 minutes after the interval.
Brazilian duo Ponte Preta and Vitoria started their Copa Sudamericana campaign on the right foot, with Ponte Preta celebrating a 2-1 triumph at Criciuma.
Ponte Preta took a fifth minute lead thanks to Cesar's header and Chiquinho doubled the lead with a 66th minute free-kick.
Joao Vitor reduced the deficit with a header two minutes from time and gave debutants Criciuma some hope ahead of the second leg.
Meanwhile in Salvador, an 88th-minute free-kick from defender Fabricio gave Vitoria a 1-0 triumph over Coritiba.
Finally in Santiago, the 2011 Copa Sudamericana champions Universidad de Chile played out a 1-1 draw with Ecuador's Independiente del Valle.
Isaac Diaz netted Universidad de Chile's goal in the 42nd minute, but Henry Leon equalised just after the hour mark.