That is the claim of Lotus team boss Eric Boullier, following a tumultuous period for fellow Frenchman Grosjean, whose career has been in doubt due to his multitude of early-race incidents on his return to the sport in 2012.
Boullier told RMC Sport after the Indian grand prix: "Romain did a great race, doing what was expected of him.
"He did a good start. He was able to fight and win places. He drove well with no errors.
"I think he has really showed his potential and that he has his place. His confidence has taken a big leap forwards, he is more calm now and he will build on it," he added.