The transposition of the great arteries (TGA) is a complex congenital heart disease which usually presents as cyanosis in neonates with limited mixing between the systemic and pulmonary circulatory systems. A delayed diagnosis of TGA can lead to ventricular failure. We report a six-week-old infant who was admitted to the paediatric Intensive Care Unit of the Royal Hospital, Muscat, Oman, in 2016 for bronchiolitis. During admission, she was incidentally diagnosed with TGA and coarctation of the aorta. Postnatal screening, including the use of pulse oximetry, plays a significant role in avoiding a late diagnosis of TGA; however, this screening tool is not widely used in Oman. Moreover, the common practice of applying a pulse oximetry probe only to the foot may have been limited in the current case due to the reverse differential saturation between the upper and lower limbs caused by this particular combination of lesions.