In December, he represented Australia at his second World Short Course Championships in Doha. On night 1, Mahoney, Matthew Abood, Cameron McEvoy and Tommaso D'Orsogna finished 5th in the 4 × 100 metre freestyle relay. The following morning he placed a disappointing 21st in the 400 metre individual medley in a time of 4:12.21. Illness stuck Mahoney and as a result withdrew from his remaining events – the 100 and 200 metre individual medley and the 200 metre backstroke.