Police are hunting three men in connection with a “vicious and unprovoked” assault in Haydock.
The 18-year-old victim was attacked as walked along Andover Road, with all three punching and kicking him as he lay on the ground.
They then fled the scene leaving the teenager with multiple injuries.
Det Insp Jason Pye said: “This was a cowardly, senseless and totally unprovoked attack on a young man going about his daily business.
“We are determined to bring the culprits to justice and appeal to the public for help in finding the three men we want to question in connection with the incident.
“The images we have from the CCTV are excellent and I am sure there will be somebody out there who can identify these people and lead us to them.
“If you can help us call Merseyside Police on 0151 777 6890 or call Crimestoppers in confidence on 0800 555111.”
The attack took place on April 5 at around 5.50pm.