Mexico stunned Brazil to win their first gold in the Olympic men\'s football tournament as Oribe Peralta\'s double clinched a shock 2-1 victory over the five-time world champions here Saturday. Peralta struck after just 30 seconds and the Mexican striker sealed one of the all-time great Olympic upsets when he scored again late in the second half. Hulk got one back in stoppage-time but Mexico, playing in their first Olympic final, were deserved winners as Brazil once again failed to end their long wait for a first football gold.