It happened about 2:20 a.m. Sunday at the Sunoco station on Maryland Avenue. Troopers say the driver was pumping gas when a man and a woman approached him and asked for a ride.
After driving the two a short distance, the victim was hit in the head with an unknown object by the male suspect. After being repeatedly hit, the victim got out of the car.
The couple drove off. The car was found hours later in Philadelphia.
The victim was treated at a local hospital for cuts to the head.
Police are looking for a black male in his early 20s, approximately 5'11" tall with an average build, and a black female in her late teens to early 20s, approximately 5'6" tall with a large build.
Anyone with information about the case is asked to contact the Delaware State Police Troop 2 Robbery Unit at 302-834-2630 extension 6, or by using the Delaware State Police Mobile Crime Tip Application available for download at http://www.delaware.gov/apps/.
Information may also be provided by calling Delaware Crime Stoppers at 1-800-TIP-3333, via the internet at www.tipsubmit.com, or by sending an anonymous tip by text to 274637 (CRIMES) using the keyword "DSP."
The Associated Press contributed to this report.