McManus started strongly in the 2015–16 season, reaching the quarter-finals of the first event, the Riga Open, with wins over Stephen Maguire, Judd Trump and others before losing to the eventual champion Barry Hawkins 2–4. As McManus did not enter the Australian Goldfields Open, his first ranking event of the season came at the Shanghai Masters. He defeated Rory McLeod 5–4 to qualify for the tournament, and then defeated wildcard Yao Pengcheng 5–2, before losing 1–5 to Ding Junhui.