The men robbed Hopps Express No. 2, Elm Street, of a substantial amount of money, Shelbyville police said.
Several people saw the men running from the convenience store and followed them for several miles before losing their trail north of Shelbyville.
The clerk told police the suspects entered the store at 9:20 p.m. and went behind the counter.
"The clerk threw a money bag at the subjects and then put his hands up in the air," officer Chris Vest said in his report. "The first subject grabbed a box of change. The second subject grabbed the money bag."
One of the men, who had what Vest described as a "black long frame weapon," is seen in store security video as black, wearing a white shirt around his face area, a gray shirt with green lettering on the back, black pants and black shoes.
The knife-wielding suspect is black and wore a pink knit cap over his face, a black long-sleeved shirt, blue jeans and black shoes.
As officers were alerted to the robbery by the store's alarm, several witnesses saw the men running from the building.
One of the witnesses, who was pulling into the parking lot, saw one of the men drop and grab the money bag as both ran behind the store to a blue Chevrolet Corsica.
While that witness called police, a truck containing several teenagers followed the car from Colloredo Boulevard to a home on Greystone Way, a dead-end street off Nashville Dirt Road.
The teenagers told officers they pulled into a driveway and turned their lights off, waited until the car left, and followed it again out Nashville Dirt Road until losing sight of it near Living Stones Church.
The pink knit cap fell from the car, was picked up by the teenagers and taken back to officers at the store.