A late lean injection system transition piece includes a flowsleeve interface extending circumferentially around a transition interior. Also included is an impingement sleeve mounting surface extending circumferentially around the transition interior. Further included is a plurality of fuel injectors integrated substantially within the transition piece and disposed between the flowsleeve interface and the impingement sleeve mounting surface. Yet further included is an inner surface extending circumferentially around the transition interior, wherein the inner surface is spaced radially inward of the flowsleeve interface and the impingement sleeve mounting surface.