Lincolnshire Police would like to hear from anyone who witnessed an assault in Hornsby Road, Grantham, just after 1pm yesterday.
A 25-year-old man was walking along Hornsby Road when he was approached by another man who then assaulted him in an apparently unprovoked attack.
The victim suffered a fractured jaw and cheekbone as a result of the attack.
A 24-year-old man has been arrested on suspicion of GBH in connection with the incident and will be questioned by police.
Officers investigating the incident would like to hear from anyone who may have seen the assault to help build up a bigger picture of what happened.
Anyone with any information relating to the incident is asking to contact DC Julia Langridge at Lincolnshire Police on 101 quoting incident 235 of July 16.