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Ronnie O'Sullivan has Stephen Hendry's record of seven world snooker titles in his sights.
The 'Rocket' clinched his fifth championship at the Crucible in Sheffield despite playing only one competitive match in the previous 10 months.
He has recently courted controversy with his comments over match-fixing - the latest chapter in a rollercoaster career analysed in his new autobiography, Running.
Here, he speaks to BBC Sport about his snooker ambitions, his father's imprisonment and the psychiatrist who helped turn his life around.
Breaking the mould
Victory in May brought O'Sullivan his fifth title following triumphs in 2001, 2004, 2008 and 2012.
"I've got five world titles. I was happy with four. I haven't set myself a mental target. It's something I would like to achieve, it would be a dream for me to get to seven, possibly eight," said the 37-year-old.
Multiple world snooker title winners since 1970
"It is definitely one of the main motivations why I still keep playing. It does drive you on. If I get to six, I'd be with Steve Davis and if I get to seven I'm there with Stephen Hendry, the greatest to have played the game.
"When you're 70 or 80 and they call you back to the Crucible as a seven-times world champion, seven sounds better than five. So there's definitely an incentive to want to win more. But the competition's tough, there's some great players out there and everyone wants to be world champion.
"I start to think, I'm nearly 40, I'm an old man. I'm getting grey hairs now. I look around and everyone's 25, 26, and I'm nearly 38 and I'm giving them a run for their money. I'm like dad on the circuit.
"I feel like I've broken the mould of players that got to their 30s and never managed to win any more titles. Maybe the next generation will think you don't hit your peak until you're 37 because Ronnie's proved it."
Relationship with Ronnie Senior
O'Sullivan's father Ronnie senior, who had encouraged him to embark on a snooker career, was jailed for murder in 1992 after a nightclub row and released in 2010.
The year after he was imprisoned, his 17-year-old son brought the UK Championship trophy to him in jail after becoming the youngster winner of a ranking tournament.
"He was telling everybody when I was 10 that I was going to be world champion," said O'Sullivan. "He has a massive amount of confidence in me.
"I was blessed with a good work ethic because of my father's influence. He always pushed me to make the most of my time at the snooker club.
"If I was caught playing the fruit machine or playing cards, I was either banned from going to the club for a while or got a stiff telling off."
Weight of expectation
O'Sullivan graduated to the professional snooker tour alongside subsequent world champions John Higgins and Mark Williams, but felt pressure to perform with his dad in prison.
The highs and lows of O'Sullivan
"I had a really good first qualifying season at Blackpool [in 1992] where I won 74 out of 76 matches and then straight after that my dad got sent down and it sunk in that he wasn't going to come out for 20 years," he reflected.
"When I won my first UK tournament, it was the worst thing that could happen to me because I got success early and the spotlight was on me.
"There was always pressure on me to win and I learned to deal with that, but what I couldn't deal with was my dad had gone away and I didn't want him to feel the guilt of me failing, so there was that extra pressure to succeed.
"It was really hard - the most difficult time of my life, to be honest with you. It was make or break for me - I could have gone one way or the other.
"At one stage I was on a downward spiral for about six or seven years. I was present at tournaments, but I was really struggling to deal with things."
Running man
After a spell in the Priory Clinic during 2000 to kick a drugs habit, O'Sullivan later found a new focus with running.
"I got myself in the Priory - which was a good start - and then found running, which is the biggest thing that has kept me together," he said.
"Snooker tournaments became a chance to visit different running clubs and running friends. It became a hobby for me around 2004 or 2005. As long as I had my running kit, I'd take my cue and think running comes first.
"When I turned up and won a five-mile race and got my £80 voucher, I was buzzing, The very first race I did I came about 100th out of 200 and then six years on I won it - and I was pretty chuffed with myself.
"In some ways, I got more sense of achievement out of my running because there was always something to gain.
"In snooker, if I didn't win it was always that I hadn't fulfilled my true potential or everyone else's expectations. I think I've got far more satisfaction out of running, and doing good races, than I have out of my snooker."
Mind games
O'Sullivan credits much of his current stability to the help of psychiatrist Dr Steve Peters, who has helped top cyclists including Sir Chris Hoy and Sir Bradley Wiggins.
Peters works with clients on what he calls their 'inner chimp' - controlling their emotional side during competition.
"I owe everything to Steve. I wasn't going to continue playing. I'd had enough come 2011 with some poor results, a lot of off-the-table stuff and I just fell out of love with the whole thing," said O'Sullivan.
"Steve turned my thinking around. I found a new zest for the game, a new enthusiasm, I was much more able to put whatever was going on in my head aside, while I was playing.
"Before, I'd just be overrun with 'I've had enough, I don't want to be here, I hate this place, I've had enough of snooker' and play snooker like I just wanted out. Now, I still think that, but we'll deal with that later, not during the match."
O'Sullivan says he keeps a diary, makes notes during sessions with Peters, records them and listens back. He feels more in control - "machine-like" - at the table.
"I wasn't sure if it was going to work for me because I'd tried everything else. Steve came at it from a different angle.
"Very rarely would we talk about snooker, but how the mind functions. He's been able to give me a better idea of how that works, so now I'm able to go away and do it all for myself."
A snooker genius?
"Snooker player. I have a degree in snooker and I am a genius.. ha." So says O'Sullivan's profile on his Twitter account.
"That description - 'most naturally talented player' - yeah, I have talent to play the game, but there were a lot more juniors around that were more talented than me who didn't apply themselves," he said.
"I've worked really, really hard and anyone who's seen me practise will know how hard I work. They realise it's something that does not come easily.
"When my dad went away that always stuck with me - the work ethic, to keep fit, and to balance it with my life as a professional snooker player which meant playing four or five hours a day."
Hitting a peak
O'Sullivan is self-critical, but says he played his best snooker at the 2012 World Championship.
"I got really ill with glandular fever just before I won the championship. I could hardly practise. I left my cue on the table at the club and didn't have it in me to do two or three hours' practice," he recalled.
"There were times in every match where I hit a ball and thought I couldn't miss. Every time I came to the table, I thought about clearing up.
"To have that confidence was unbelievable. That's how I was as a young boy, and that confidence has come back.
"I played OK in 2013, not great. I struggled through to the final. Then I played a really good final.
"To go and win it was a fairytale and is probably one of my greatest achievements.
"I was pushed internally. My mind was on one ball at a time. There were times when I felt I wasn't up for this, lacking the match practice and had to dig deep. Come the final I actually started to feel like a snooker player again, started to play from instinct."
Interview: Jamie Broughton Words: Frank Keogh