Former Olympic champions Argentina were made to toil by world No.14 South Africa before registering a 1-0 win in the opening Pool A match of the FIH men's hockey World Cup here on Friday.
After a barren and hard-fought first two quarters, Argentina, the 2016 Olympic champions, scored the winner in the 42nd minute through a field effort from Casella Maico.
But it was far from rosy for the Los Leones as it was South Africa who pressed hard in the first quarter but failed to convert their chances into positive results.
In the second quarter, Argentina came back strongly and secured three penalty corners in succession but wasted all as South Africa defended stoutly.
After the change of ends, South Africa had the first shy at the goal in the form of a penalty corner but the opportunity was wasted.
Argentina broke the deadlock in the 42nd minute when Casella capitalised on a counter-attack and scored a brilliant field goal from Toscani's pass.
Down a goal, South Africa came out attacking in the fourth and final quarter, but the Argentine defence stood firm to stifle their rivals' forays and register a hard-fought win.
Argentina will face world No.1 Australia on January 16, while South Africa will take on France in their next pool match on the same day.