Indian driver Narain Karthikeyan has described double world champion Sebastian Vettel as a "cry baby" following their collision during last Sunday's Malaysian Grand Prix.
Red Bull's Vettel finished a lowly 11th in a chaotic rain-disrupted race at Sepang and called Karthikeyan an "idiot" after the collision with the HRT driver that cost Vettel a place in the points.
Karthikeyan, India's first Formula One driver, said it was a "shameful" response from a world champion who is not known for being particularly outspoken.
"It is really unprofessional," the Indian told the Hindustan Times.
"For a driver who has achieved so much, to take out his frustrations on me just because he is having a difficult year is really sad. One does not expect a professional sportsman to be such a cry baby."
Vettel is sixth in the overall driver standings after the first two rounds of the new season, suggesting his, and Red Bull's, dominance is over.
Karthikeyan did not blame Vettel for the collision, calling it a racing incident in which neither driver was at fault.
Formula One has been followed closely in India since 2005, when Karthikeyan raced for the now-defunct Jordan team.
He returned to the circuit in 2011 following a deal with the Spanish Hispania racing team, now known as HRT.