Muir's first match as a professional was a 5–1 loss against two-time world champion Mark Williams in qualifying for the 2013 Wuxi Classic.&lt;ref name="2013/14"&gt;&lt;/ref&gt; His first wins came in qualifying for the next event, the Australian Goldfields Open, by defeating James Cahill and Rod Lawler both 5–1, before losing 5–2 to Liam Highfield. At the Asian Tour event, the Zhangjiagang Open, he defeated world number seven Ding Junhui 4–3 in the last 32 by compiling a break of 80 in the final frame, before being whitewashed 4–0 by Da Hailin in the next round. Muir could not win a match in ranking event qualifying in the rest of the season until the final event, the World Championship, when he beat David Grace 10–6, but then lost 10–5 against Nigel Bond in the subsequent round. Muir finished his debut season on the main tour at world number 113.