Police have launched an investigation after a man was found with "unexplained" injuries.
Merseyside Police said the man, who is in his 20s, was found with a head injury on a park off Valentine Road, Newton, shortly after 5pm on Monday.
Police officers and paramedics treated him at the scene before he was taken by ambulance to Whiston Hospital, where he was found to have a bleed on the brain.
His condition has been described as "serious but stable".
Detectives and local patrol officers are carrying out enquiries in the area to establish how the man came about his injuries.
Anyone with information is asked to contact Merseyside Police on 101, quoting log 819 of December 4, or Crimestoppers, anonymously, on 0800 555 111.