A shopworker tried to stop a would-be thief by kicking over his motorbike, a court has heard.

William Collins, 33, is facing "inevitable" jail for his attacks on two members of staff at stores in Dumbarton and Alexandria.

At 8.45am on June 15 he went into the Morrisons Daily in Lomond Drive, Dumbarton, dressed in a black hooded jumper with the hood up.

A struggle ensued over a glass bottle of alcohol before Collins struck an employee's face with it.

The worker was taken to hospital and treated for a small laceration that will leave a scar.

Twenty minutes later, Collins went into the Morrisons Daily in Argyle Street, Alexandria.

He tried to pick up a case of Tennents lager but was told alcohol couldn't be sold before 10am.

The man started to walk towards the front door but a member of staff stood in front of him with his hands out to stop him.

Outside, the worker tried to stop Collins again by kicking over his motorbike and Collins raised the case of lager and a carrier bag in the air.

The case burst open, sending cans to the ground.

The worker ended up on the ground and Collins kicked him to the head. Police found the victim covered in blood and he had a laceration under his eye that will also leave a scar.

At Dumbarton Sheriff Court on October 29, he pleaded guilty to assaulting a member of staff of Morrisons Daily, Dumbarton, by striking him on the head with a glass bottle to his severe injury and permanent disfigurement.

He assaulted a worker at the Morrisons Daily in Alexandria and attempted to strike him on the head with a case of lager, causing him to fall to the floor and repeatedly kicked him on the head to his severe injury.

The Crown accepted he was not guilty of attempting to steal two bottles of Glens Vodka and a case of Tennents.

He was also not guilty of struggling with a second member of staff in Alexandria, pushing him on the body and causing him to fall to the floor.

Collins further pleaded not guilty to using a motorbike without insurance, without a valid licence, to having a knife and to refusing to give a blood or urine specimen when required by police. Prosecutors accepted those pleas.

Listed as a prisoner of Low Moss, Collins' defence solicitor, Kenny McGowan, accepted his client's record was "significant".

He said alcohol featured in his life but did not "diminish his responsibility".

Sheriff Frances McCartney said there was "no alternative to custody" and it was "inevitable".

Sentence was deferred until November 26 for reports. Family supporters blew kisses and said "love you" as Collins was led to the cells.