Williams first ranking event of the 2012–13 season was the Wuxi Classic, where he beat Tom Ford and Mark Allen, before losing 3–5 to Marcus Campbell in the quarter-finals.&lt;ref name="2012/13"&gt;&lt;/ref&gt; He went one better at the Shanghai Masters by seeing off Mark Davis, Ricky Walden and Joe Perry to face Judd Trump in the semi-finals. Trump was 5–1 up and on a break of 53 for the match, but Williams came back to trail 4–5 before losing the next frame to come up short of completing a comeback, and Trump beat Williams 6–4. Williams then suffered a huge dip in form as he lost in the first round of six successive ranking events; after his defeat to Mark King in the 2012 UK Championship he suggested that he was contemplating retirement. During his string of defeats he did beat Matthew Stevens in the non-ranking Masters from 1–4 down (Stevens also missed a pot for 5–1), but then lost 1–6 to eventual champion Mark Selby. At the China Open in March Williams won his first match in a ranking event since September with a 5–2 victory against Lü Haotian and continued his run by defeating Ali Carter 5–4, before losing 1–5 to Selby in the quarter-finals. At the World Championship he lost 6–10 to debuting compatriot Michael White in the first round and admitted afterwards that the season had been one he would be looking forward to forgetting, but he was committed to playing next year. His poor season saw him drop 12 places in the rankings to world number 15.