Stephen Armstrong pleaded guilty to committing that offence in Edinburgh Road in Cockburnspath on October 20.
Jedburgh Sheriff Court was told he had a breath-alcohol reading of 66 microgrammes, the legal limit being 22.
He also admitted assaulting a police officer by placing him in a headlock and seizing his hand before digging his nails into it to his injury at his former home in Coldingham.
Armstrong, now living in Main Street, Tweedmouth, Northumberland, will be sentenced on March 2.
An interim driving ban was imposed.