Merseyside Police has arrested a 17-year-old male on suspicion of section 18 wounding with intent.
An arrest was made in Cheshire on Monday 31 October and the male has since been released on conditional bail, pending further inquiries.
The arrest follows a police investigation following reports that a 19-year-old man was stabbed in Rock Ferry.
It is believed he was assaulted in Devon Gardens, Old Chester Road, Rock Ferry earlier in the day.
The teenager self-presented at hospital with an injury to his body at around 4.35pm on Sunday 30 October. His injury is not believed to be life-threatening.
Merseyside Police is still calling on anyone who can assist with the investigation to DM @MerPolCC or contact @CrimestoppersUK on 0800 555 111 quoting reference 22000797349.