B737-800
Situational Awareness
Ground Incursion Runway
Flight Crew Took Evasive Action
Human Factors
We were cleared for takeoff at MIA; and had just advanced the throttles to T/O thrust when a white; unmarked MD-80 taxied across our departure runway from left to right about 800 feet down the runway from us. I retarded the throttles to idle; disconnected the autothrottle; and applied brakes. We had barely moved at all. We then waited for the intruding aircraft to clear the runway; confirmed our take off clearance with the Tower; and took off uneventfully. Simply: had we not noticed the intruding aircraft immediately; this event could have had a tragic ending.
B737-800 flight crew cleared for takeoff at MIA airport noted an aircraft crossing the departure runway down field and rejected the takeoff.