A combustor includes a combustion chamber that defines a longitudinal axis. A primary reaction zone is inside the combustion chamber, and a secondary reaction zone inside the combustion chamber is downstream from the primary reaction zone. A center fuel nozzle extends axially inside the combustion chamber to the secondary reaction zone, and a plurality of fluid injectors circumferentially are arranged inside the center fuel nozzle downstream from the primary reaction zone. Each fluid injector defines an additional longitudinal axis out of the center fuel nozzle that is substantially perpendicular to the longitudinal axis of the combustion chamber.