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 second of the season after Robertson), and also the twelfth player to win the World and UK Championship double in their career. In winning the world title, Selby also retook the world number one spot. In the first ranking event of the season, the Wuxi Classic, Selby lost 3–5 to Liang Wenbo in the last 32. He won the minor-ranking Riga Open, defeating Mark Allen 4–3 in the final, but lost 5–6 to Allen in the semi-final of the ranking Shanghai Masters. He suffered a surprise early exit in the last 128 of the ranking International Championship when 19-year-old tour