Argentina set up a tantalising Copa America semi-final against hosts Brazil after easing past Venezuela 2-0.
Martinez’s instinctive 10th-minute finish was his sixth goal in 10 international appearances and due reward as Lionel Scaloni’s men made a rapid start.
Lionel Scaloni’s side had to weather a series of attacks from Venezuela in the second half and it took a strong save from Franco Armani to prevent Ronald Hernandez from levelling.
Substitute Lo Celso capitalised upon an error from Venezuela goalkeeper Wuilker Farinez to settle matters at the Maracana – the stadium where Argentina lost the 2014 World Cup final to Germany.
