The pair lost the tennis mixed doubles bronze medal play-off, going down 6-1, 7-5 to Lucie Hradecka and Radek Stepanek of the Czech Republic in just 71 minutes.
Mirza and Bopanna had lost in the semi-finals Saturday to Venus Williams and Rajeev Ram of the United States.
It was a third tennis bronze in Rio for the Czechs after Petra Kvitova in women’s singles and Lucie Safarova and Barbora Strycova in the women’s doubles.
“The Olympics is only ever four years. I don’t know if I will be still playing in four years,” said the 29-year-old who was on the verge of tears as she addressed the media under a sweltering Rio sun.
“We didn’t play our best, but that’s sport. It’s going to take some time to get over this. We had chances and in the second set we could have won multiple times.
“There’s not a lot I can say to you guys at the moment.” It was a disappointing tennis event for India in Rio.
Leander Paes, playing in his seventh Olympics, and Bopanna lost in the first round of the men’s doubles. Mirza and Prarthana Thombare were defeated in the second round of the women’s doubles.
India were still without a medal on Sunday and staring at their fourth washout in recent times having failed to medal in 1984, 1988 and 1992.
They have won just two golds in 36 years — men’s hockey in the boycotted Games in Moscow in 1980 and men’s shooting at Beijing in 2008.
For 37-year-old Stepanek, winning bronze felt just as good as winning the Davis Cup.
“I can compare this with the Davis Cup finals, where we were a couple of years ago because I think the nicest, deepest and strongest emotions you can only achieve when you play for your country,” said the Czech who performed a ‘crab’ dance in the media mixed zone before breaking into his version of Queen’s Radio Ga Ga.
“I would recommend everyone to at least go through it once. It is something amazingly special. This medal belongs to our whole country.
“I’m slowly losing my words because I am slowly starting to realise what we have achieved and maybe at the end of the mixed zone I am going to cry.”