Abstract <p>The present experimental study focuses on exploring the decay characteristics of a Mach 0.6 jet ejected from a rectangular orifice of the aspect ratio (AR) equal to 2 under the influence of secondary injections in two configurations: injection along minor (IAM) and injection along diagonal (IAD). The secondary injections were introduced at three Mach numbers, namely, M_s = 0.8, 0.9, and 1.0. The total pressure decay along the streamwise direction (<i>X</i>), along longer (<i>Y</i>: major) and along shorter (<i>Z</i>:&#xa0;minor) directions have been measured to evaluate the jet decay and spreading characteristics. Axis-switching locations for the free and controlled jets were determined based on the evolution of the non-dimensional jet half-width (<i>B</i>*). The rectangular orifice jet displayed a shorter potential core (2.8<i>D</i>_eq) when compared to that of a rectangular nozzle jet at the same aspect ratio and Mach number. The IAD is found to shorten the potential core and accelerate jet decay, whereas IAM destroys the potential core entirely, leading to rapid near-field mixing and early axis-switching, with a maximum upstream shift of 77%, observed at M_s = 1.0.</p>