Mark Selby with a shock 3–5 defeat to Andrew Pagett in the qualifying rounds of the 2013 Wuxi Classic. The tournament was the first to use a new format that required top-16 players to compete in qualifiers. In minor-ranking tournaments, Selby was runner-up in the Yixing Open, where he lost 1–4 to Joe Perry, and the Rotterdam Open, where he lost 3–4 to Mark Williams. He won the Antwerp Open, defeating Ronnie O'Sullivan 4–3 in the final. In December, in the seventh frame of his UK Championship semi-final against Ricky Walden, Selby compiled snooker's 100th officially recognised maximum break in professional competition.
Mark Selby the final and eventually won 18–14. His second World Championship crown saw him finish at number one in the world rankings for the fifth year in a row. Selby won his first title of the season at the Paul Hunter Classic by beating Tom Ford 4–2. His semi-final with Stuart Bingham at the Shanghai Masters was a meeting between the top two ranked players in the world and Selby won 6–5, having been 5–3 behind. After taking an early 3–1 advantage over Ding Junhui in the final, Selby was ousted 10–6. He was beaten 6–2 by Judd Trump in the