The Reds are preparing for the loss of current physio Richie Partridge after he agreed to take up a role with the Qatar national team.
The Irishman, who made three first-team appearances at Anfield in the early 2000s, will end his latest stay on Merseyside in March.
But the blow of his departure has now been softened with another high-profile appointment from a Premier League rival.
Lilley’s arrival comes hot on the heels of Liverpool’s recent swoop for Arsenal doctor Gary O’Driscoll.
O’Driscoll will also join the Reds next month, replacing head of medical services Andy Massey once he begins a new role at Fifa.
Lilley, who has also previously worked for Norwich City, will link up with a familiar face upon his arrival at Anfield in Lee Nobes.
Liverpool’s head physio made the same switch from the Etihad Stadium to Anfield in November 2018 after 11 years in Manchester.