Hyperpolarized dissolved-phase 129Xe imaging allows pulmonary gas transfer processes to be quantified at multiple stages and physical abnormalities in gas-exchange to be identified in subjects with pulmonary disease. However, the technique is hindered by gas-phase contamination due to imperfect frequency-selective excitation of the 50-fold larger pool of gaseous 129Xe. The previous method to remove this contamination required additional echoes. We present a simple post-acquisition method to remove gas-phase contamination with >90% efficiency. This method can be applied to the standard gas-transfer MRI sequence, thus permitting contamination removal for existing data, facilitating more accurate and consistent hyperpolarized 129Xe gas-transfer imaging.