The 43-year-old actor, who is the new addition to the sequel of 2012 suspense thriller, took to Twitter to share the picture of his knee.
"Busted my knee today, while filming a chase sequence. Finished the shoot. Now in agony. But then #nopainnogain #kahaani2," he wrote.
This is the first time Rampal and Balan are teaming up together for a film.
Co-written and directed by Sujoy Ghosh, "Kahaani 2" went on floors in March this year. It is expected to hit theatres in November this year.