Police identified the officer as Lucia Wade, a six-year Police Department employee and a police officer for three years.
Sgt. Lisa Banayat said Wade and another officer were making a security check at the Denny's restaurant on Baker Avenue at about 5:30 p.m. Sunday when she recognized 43-year-old Manuel Santiago as a robbery suspect from a crime bulletin.
Santiago is suspected of pushing a man to the ground and stealing his cell phone in the 500 block of Barham Avenue on Saturday, police said.
When Wade approached him and tried to detain him, Santiago ran across Santa Rosa Avenue. Wade chased him and was struck by a northbound car.
Santiago was caught about 10 minutes later and was booked into the Sonoma County jail for robbery and battery with serious bodily injury stemming from the Barham Avenue incident, and for felony resisting arrest for the Santa Rosa Avenue incident, Banayat said.
Santiago is scheduled to be arraigned in Sonoma County Superior Court Wednesday afternoon.
The driver pulled over after striking the officer and was interviewed and released, Banayat said.