He received the Thai nomination to compete on the snooker tour for the 2012–13 season. As a new player on the tour, he needed to win four matches to reach the main stage of the ranking events. He lost in the third qualifying round in three of the first four ranking events of the season.&lt;ref name="2012/13"&gt;&lt;/ref&gt; In September, it was announced that his match at the Players Tour Championship – Event 3 against Steve Davis was under investigation due to unusual betting patterns. Un-Nooh moved from an 8/11 odds-on favourite to 11/8 against just before the match started, and went on to lose 0–4 to the six-time world champion. World Snooker released a statement in November to confirm that there was insufficient evidence, and that no further action would be taken against Un-Nooh. He reached the final qualifying round for the UK Championship and the World Open, but lost to Michael Holt and Ryan Day respectively. Un-Nooh played in nine of the ten Players Tour Championship Events during the season; his best results were three last-16 defeats in European Tour Events, and he finished 46th on the PTC Order of Merit. His season ended when he was beaten 3–10 by Ben Woollaston in the third round of World Championship Qualifying, which saw him finish the year ranked world number 69.