Mark Selby Open, losing 1–4. Selby won his first ranking title of the 2017/18 season by retaining the International Championship after surviving a fightback from Mark Allen, who trailed 3–8 and 7–9 in the final but the Englishman prevailed 10–7. As 2017 World Snooker Champion, Selby automatically qualified for the 2017 Champion of Champions. However, he lost in the quarter-finals to Luca Brecel by a scoreline of 4–6. At the 2017 Shanghai Masters, Selby crashed out to 2011 finalist Mark Williams in the quarter-finals 3–5. Selby's reign as the UK champion came to an end with a 3–6 defeat to Scott Donaldson
Mark Selby 3–5 first round defeat to Jamie Burnett in the Australian Goldfields Open. Selby lost his world number one spot to Judd Trump after the latter's victory in the inaugural International Championship in China. However, just five weeks later, Selby won his third ranking title and largest of his career, the UK Championship, to regain the top spot. He defeated Michael White 6–3, Ryan Day 6–4 from 3–0 down, and Neil Robertson 6–4 from 4–0 down to reach the semi-finals, where he beat Mark Davis 9–4 to progress to the final. Already assured of overtaking Trump regardless of the result, Selby