At around 5:45pm, a man was walking along Rodney Street, near to its junction with Bairds Brae, when he was struck by a BMW, travelling westbound.
Emergency services attended and a 51-year-old man was taken to Glasgow Royal Infirmary where medical staff describe his condition as serious.
The driver of the car was uninjured but has been left badly shaken by the incident.
Officers are appealing for anyone with any information regarding the incident, in particular, any dash cam footage.
Enquiries continue to establish the circumstances of the crash and anyone with information is asked to call Road Policing Officers in Glasgow via 101, quoting incident number 2766 of Tuesday, February 4, 2020.