كتب : Omar AbdelAziz
The Athens 2004 gold medalists needed a second half striker from Angel Di Maria, who slotted home after being set up by Lionel Messi.
With a 42c temperature, the referee had to stop play twice at Bird's Nest Stadium so that player's can have water.
However, the South American giants avenged their Atlanta 1996 final defeat to the Super Eagles, who claimed their first silver medal this summer.
Brazil won the bronze medal after thrashing Belgium 3-0 on Friday.