Under Venezuela's constitution, Diosdado Cabello, head of the National Assembly, is the man who would assume presidential powers until a new president is elected and sworn in.
But Hugo Chavez preferred Vice-President Nicolas Maduro as his successor and when the president's death was announced, Mr Cabello did not appear on the podium.
Nevertheless, he was close to the late leader and is considered a possible candidate for office.
Well connected in the world of politics, business and the military, Diosdado Cabello was long part of Hugo Chavez's inner circle.
The stocky former soldier, whose first name means "God-given", took part in the failed coup in 1992 that first brought Hugo Chavez to public attention.
The pair, who met in Venezuela's military academy, were jailed after the botched attempt to remove then-President Carlos Andres Perez from power.
Mr Cabello went on to become a major player in what President Chavez calls his "Bolivarian revolution".
It was during another coup a decade later that Mr Cabello's allegiance to President Chavez was tested.
Diosdado Cabello was Vice-President when Mr Chavez was ousted for 48 hours.
Mr Cabello became the de facto President, but it was one of the shortest terms of office on record.
His first order was to send a group of elite navy troops to rescue Mr Chavez, who was being held prisoner by renegade forces at a base on a Caribbean island.
Mr Cabello's loyalty was rewarded, serving as interior and justice, infrastructure and public works minister.
He also governed the state of Miranda from 2004 until 2008, when he was defeated by opposition candidate Henrique Capriles.
In 2011 he became Vice-President of the United Socialist Party (PSUV) making him the second most powerful figure in the party after Hugo Chavez.
In early 2012 he was appointed president of the National Assembly and was then re-elected in January 2013.
Politics runs in Mr Cabello's family. His wife, Marleny Contreras, is a congresswoman and his brother, Jose David Cabello, is currently the head of Venezuela's tax authority Seniat.
The political opposition has questioned Diosdado Cabello's business interests and has painted him as one of the "boli-bourgeois" - those who have made good under President Chavez.
No love lost
Nelson Lanz, a journalist for the pro-Chavez website aporrea.org has described Mr Cabello as "the man most hated and vilified by the opposition and not much loved by Chavistas (supporters of President Hugo Chavez)".
"Diosdado Cabello, despite his loyalty, has been a stone in the shoe of the president, since he's a man with a lot of influence over some civil servants and he's known how to position them in key posts in the administration," Mr Lanz wrote.
Nevertheless, Mr Cabello remained close to President Chavez.
He seemed to accept Mr Chavez's decision to name Nicolas Maduro as his preferred successor.
Mr Maduro and Mr Cabello have stood shoulder to shoulder, giving updates on the president's health as he underwent more surgery in Cuba.
But with his contacts in the military, the government and among some business people, Mr Cabello wields considerable power and is thought to harbour his own political ambitions.