The 20-year-old, currently ranked world number 54, will next face Japan's Jun Mizutani, who eliminated Panagiotis Gionis of Greece 4-1.
Calderano's opponent Tang made a series of mistakes under the glare of an increasingly raucous audience, who stomped their feet and booed loudly as he served.
Calderano said he was happy to capitalise on the home advantage.
"I didn't put limits on myself, I knew I had the potential so I just tried to keep focussed on every match," he said.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
"I never imagined that we would have a crowd as big as this and so loud in Brazil for table tennis, it's looking like a soccer stadium ... I hope the crowd is messing up with the minds of my opponents and I hope they keep like that."
Gold medal favourites China breezed through their matches in the men's and women's singles, with Ma Long and Ding Ning spending just a combined 30 minutes each defeating Denmark's Jonathan Groth and Romania's Elizabeta Samara.
In the women's singles, world number six Kasumi Ishikawa of Japan lost 4-3 to North Korea's Kim Song-i after playing through a leg injury sustained midway through the match.
(Reporting by Brenda Goh; Editing by Peter Rutherford)
