It had been presumed in recent days that the source of the accusation must have been Piquet and his famous father, still furious after being recently ousted by Renault boss Briatore.
But reports this week suggest that Brazilian Massa, who drives for Ferrari, immediately suspected that Piquet had been asked to crash on purpose so that the safety car would emerge and the sister Renault of Fernando Alonso win the race.
"He crashed in a very strange way," TV Globo commentator Reginaldo Leme is quoted as saying.
"It struck me when I was talking recently with Felipe Massa. Felipe had gone to Briatore and said, 'This crash was not right, it happened because you wanted it to'."
Leme also said other drivers had been suspicious of the Piquet crash.
Massa had led comfortably from pole position in Singapore last September until the Alonso safety car, but when he made his pitstop he then famously drove away with the fuel hose still attached.
Now recovering from injury, Ferrari's Massa lost the 2008 world championship to Lewis Hamilton by a single point.