In June 2014, Gleeson was called up to the Australian Boomers coaching staff for the 2014 FIBA Basketball World Cup. He served as an assistant alongside head coach Andrej Lemanis. He continued on as Lemanis' assistant in 2015 and 2016, as he was a part of the Boomers' 2015 FIBA Oceania Championship triumph as well as their Rio Olympics campaign.