"I've won four UK titles, four Masters and three Worlds, which is a good haul, but in my mind I have under-achieved," said the Essex player who is currently ranked 11th and has no certainty of keeping his top 16 place for the rest of the season. "I should have won two more World titles, two more Masters and maybe another UK. I've been in nine Masters finals and I should have converted another couple of those.
"I could have had Stephen Hendry's records in site, but I have had a lot of ups and downs in my career. I suppose with the mindset I have had at times, I should be happy with what I've achieved.
"I'm still excited when I look forward to the big events. I'm happy to be the underdog now, even though I would much rather be among the favourites and really fancying my chances. The other players have flown past me and rankings don't lie. I'm coming from a different place where I enjoy events and hope to nick a big scalp. There is no pressure on me to win."
O'Sullivan came through the pro ranks with John Higgins and Mark Williams, and though the trio are less than nine months apart in age, O'Sullivan feels he has fallen behind.
"Those two are still winning titles," he said. "I was doing the same until two years ago, but I'm not any more so I'm not in that category. Then you've got Mark Selby who is World No 1 and very consistent, Shaun Murphy, Judd Trump, Neil Robertson and Ding Junhui. There are eight or nine players who are winning everything, and I'm not one of them. It's touch and go whether I'll even be in the top 16 when the World Championship comes around."
O'Sullivan plays Steve Davis in the first round at the UK Championship at the York Barbican on Sunday December 4 (afternoon session). TICKETS FOR THE TOURNAMENT ARE ON SALE NOW and there is still availability for many sessions. For details call 0844 854 2757 or CLICK HERE
Saturday 3 and Sunday 4 December are student nights, with tickets for students just £5 per night. That's a huge saving of £10. To claim this offer simply quote the offer code 'stud147' when booking tickets online, in person or by phone.
Book three evening tickets between Saturday 3 and Wednesday 7 December for just £21 (saving £24!). Tickets do not need to be consecutive evenings. To claim this offer quote the code 'Eve321' when booking tickets. Tickets must be booked in person at the York Barbican or by calling 0844 854 2757.
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He then plays Ding Junhui in the first round of the Masters at Alexandra Palace in London on Sunday January 15 at 1.30pm.
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