Police were called to Walters Way near Monument Boulevard at about 9:45 p.m. on a report of a stabbing that had just happened, Concord police Lt. Jim Lardieri said.
When they arrived, officers learned that three teenage boys had been walking on Walters Way when three male suspects, also possibly in their teens, confronted them and told them to empty their pockets.
Two of the boys complied but the third tried to run away, Lardieri said. One of the suspects caught up to the boy and stabbed him in the upper torso.
The three suspects then fled in a dark-colored vehicle, Lardieri said.
The stabbing victim was taken to a hospital and is expected to recover.
Anyone with information about the case is asked to call the Concord Police Department at (925) 671-3030. People who wish to remain anonymous can call the Police Department's tip line at (925) 603-5836 or Bay Area Crime Stoppers at (800) 222-8477.