"I have faith you will be triumphant," Erdogan told Maduro in a split screen chat broadcast on Venezuelan state television on Thursday.
Maduro, in turn, told Erdogan that "Venezuelans are going to give a lesson on democracy and liberty to the world on Sunday."
Also at a closing campaign event in the capital Caracas on Thursday, Maradona took to the stage, waving a Venezuelan yellow, blue and red flag.
The soccer legend, who has called himself a "soldier" for Maduro, is well-known for supporting anti-US politicians and was a friend of Maduro's predecessor Hugo Chavez and the late Cuban leader Fidel Castro, whose image is tattooed on his leg.
Maduro is seeking a second six-year term on Sunday. During a Caracas campaign rally, the president warned of foreign plots to mar the Sunday’s election.
"Imperialism tried to stop the elections with external threats, and could not and will not do it. [Imperialism] tried to stop the elections, with violent protests; they could not and will not be able to," Maduro told the huge crowd attending the rally.
The 55-year-old Maduro, who took power in 2013 after the death of Hugo Chavez, has survived massive anti-government protests during the past two years.
Critics blame Maduro for the deepening economic crisis in the once-prosperous country. But Caracas accuses the United States for being behind the ailing economy, saying Washington is plotting to hobble Venezuela’s economy and topple its government.
The Trump administration has threatened to impose further sanctions on Venezuela and urged Latin America to cut off the country’s officials from financial systems.
