Police otherwise reported a busy but relatively calm night as revellers either drowned woes or celebrated wins in the city's night spots after a day at the Tamworth Racecourse.

Several people tried running the gauntlet and were charged with drink driving throughout the afternoon and into the evening on the roads leading from the course into the city.

The most serious incident took place outside the racecourse's main gates at about 8.10pm among a group of young people winding down in the car park.

Police said an 18-year-old man among the group was having a "friendly argument" with another male when there was a minor altercation.

Without warning another man king hit the victim to the side of the face leaving him with a cut to the eye and some swelling.

The offender, who was a stranger, then ran into the darkness leaving the victim's friends to render first aid.

Police said the young man was treated for the injury and was believed to have suffered a fractured eye socket.

Police are working to identify the offender.

Meanwhile police charged four people with drink driving, two of whom allegedly did u-turns to avoid a roadside breath test.

A 27-year-old Oxley Vale man was charged with a low range PCA after police saw his vehicle do a u-turn about 150m ahead of their roadside stop in Britten St.

It was about 5.05pm when the man pulled up underneath a tree, claiming he was looking for a shady car park.

He was found to be a cancelled driver and was charged with a low range PCA after allegedly recording a reading of 0.06.

A 19-year-old man was charged with a special range PCA after police saw his Toyota ute do a u-turn on the same road at about 5.35pm.

Police saw the vehicle stop about 300m away prompting them to go after the driver who was on his provisional licence.

The driver stated he had just finished a beer and after the obligatory time passed, he allegedly recorded a reading of 0.04 which was above the allowable 0.02.

A 21-year-old Tamworth man was charged with a mid range PCA after he was stopped in Lockheed St at about 7.40pm.

Police allege he recorded a reading of 0.08 despite telling police he had stopped drinking beer at about 1pm.

A 20-year-old Dungowan man recorded a low range PCA of 0.055 when he was stopped at 8.35pm in Jewry St in his Mitsubishi Magna.

Police said he admitted to drinking beer at the racecourse.