In the 2009–10 season, as reigning World Champion, he lost 5–6 on the black ball to Neil Robertson in the semi-final of the Grand Prix; and 8–10 to Ding Junhui in the final of the UK Championship, after surviving a comeback by Ronnie O'Sullivan in the semi-final when leading 8–2, to advance 9–8 the previous evening. He also defeated Neil Robertson 9–8 during the tournament. He captured the Welsh Open title by defeating Allister Carter 9–4 in the final, and ended the season as World no. 1 despite an 11–13 loss to Steve Davis in round two of the World Championship.