Robertson started 2013 by attempting to defend his Masters title. He produced a comeback in the first round against Ding Junhui by taking the final three frames in a 6–5 triumph, shouting "You beauty!" when he potted the clinching red. Another deciding frame followed in the next round against Mark Allen, with Robertson making a 105 break in it to progress to the semi-finals and a more comfortable 6–2 win against Shaun Murphy. Robertson won three frames from 3–8 down to Mark Selby in the final, before Selby held off the fightback by taking the two frames he required to win 10–6. Robertson was beaten in the semi-finals of both the German Masters (2–6 to Ali Carter) and the World Open (5–6 to Matthew Stevens). Robertson's victory in the Gdynia Open earlier in the season helped him finish fifth on the PTC Order of Merit to qualify for the Finals. Wins over Jamie Burnett, Barry Hawkins, Xiao Guodong and Tom Ford saw him reach the final. He faced Ding Junhui and from 3–0 ahead went on to lose 3–4, meaning that Robertson had now lost his last three ranking finals, having won his first six.