American Canyon police were called to the 2100 block of Elliott Drive at 3 a.m. Saturday on a report of a man being assaulted.
The male victim told officers he had been "jumped" by two men who asked where he was from, then got out of their car and attacked him, giving him a bloody nose.
A short time later, police stopped a vehicle matching the description of the suspects' vehicle. Both the driver and the passenger had blood on them, but denied any involvement, American Canyon Police Chief Oscar Ortiz said Monday.
The driver, Eric Quitugua-Ignacio, 22, of Vallejo, was arrested for investigation of misdemeansor DUI.
The passenger, Samuel Camarena, 22, of Vallejo was arrested for felony violation of probation.