Shortly before 1am on Saturday, August 2, police were called to a report of an altercation on Drummond Road Skegness.
A 30-year old man from Peterborough was taken to Pilgrim but later transferred to QMC for surgery to a bleed on the brain.
A 24-year old man from Lincoln was arrested and interviewed.
He has been released on police bail while enquiries continue.
The injured man’s condition is critical but stable.
Police appeal to anyone who was in the area and has information to contact police on 101, quoting incident number 29 of Saturday, August 2.