Officers were called to the Railway pub, on Preston Road, in the early hours of Saturday morning following reports a man had been stabbed.
However detectives have since ruled his injuries were caused when the man fell on a spiked fence.
Officers were called to the scene at 12.30am and found a man covered in blood.
On Saturday morning, police confirmed they had arrested two men, aged 23 and 29, on suspicion of grievous bodily harm in connection with the incident. They have since been released.
Det Sgt Ian Derbyshire said: “Following a thorough investigation, we can confirm we are no longer investigating this incident.
“The victim’s injuries are accidental and as a result of falling on a spiked fence.
“The two men arrested have been released without charge.”
Police earlier said the man had lost a lot of blood but his injuries were not life-threatening.