A drunken man needed 10 police officers to restrain him after he took a knife into the street, a court heard.
Lee Buchanan was disturbed by two men arguing outside his flat and began demanding "compensation".
One of the men got into his car to drive away, but Buchanan clung on to the steering wheel, forcing him to stop.
The 27-year-old then grappled with the victim.
Alan Murphy, prosecuting, said: "The defendant had his hand inside the complainant's mouth, causing a cut in his mouth and on his left cheek."
Buchanan grabbed the ignition keys from the 32-year-old victim's car and ran back into his flat in Ashby Road, Loughborough. The police were called and an officer went to Buchanan's then home, in the early hours of November 11.
Mr Murphy told Leicester Crown Court: "The defendant was clearly wound up, shouting and became violent.
"He grabbed the officer in a headlock and tried to push him down the stairs. It took 10 police officers to control him."
The car keys were recovered, along with a knife.
Buchanan, of Knightthorpe Road, Loughborough, was jailed for 12 months.
He admitted causing an affray in the street, possessing a knife and assaulting the officer.
In mitigation, the court heard Buchanan had been drinking and, after previous late-night disturbances outside his home, he "snapped in a moment of madness".
