Ronnie O’Sullivan has withdrawn from the Northern Ireland Open due to medical reasons. The Rocket was due to play against Long Zehuang in the first round of the Belfast tournament, which begins tomorrow.

O'Sullivan has previously revealed that he struggles with his fitness towards the end of the snooker season. It has now been confirmed that the 48-year-old has pulled out of the Northern Ireland Open, with the World Snooker Tour (WST) citing medical reasons.

The WST confirmed O'Sullivan's withdrawal, but the seven-time world champion is yet to comment.

A World Snooker Tour statement read: “Ronnie O'Sullivan has pulled out of the BetVictor Northern Ireland Open for medical reasons

“O'Sullivan was due to face Long Zehuang in the last 64 in Belfast on Monday afternoon, but he withdrew from the event on Sunday evening. China's Long receives a bye to the last 32.”

O’Sullivan pulled out of the Northern Ireland Open and the Champion of Champions event in Bolton last year. At the time, he blamed stress and feeling ‘drained’ in the final months of the gruelling snooker season.

He has not committed to much other than the International Championship in Nanjing, China, for the remainder of this year. Speaking in Asia earlier this month, O’Sullivan insisted that he will happily pull out of tournaments the day before they begin if he does not feel fit enough.

“I will enter them and if I feel like the day before I want to go then I’ll go but if I’m not up for it then I’ll just say I’m not ready for it,” he told Virgin Radio. “They’ll always get a replacement to come in and take my place.”

O’Sullivan has all but confirmed that he will play in the International Championship, though, adding: “Possibly, yeah in November, just outside of Shanghai.

“That’s a ranking event, quite a big tournament, I’ll play in that and then I’ll go to another city in China and play in an Asian PTC event which is just for Chinese players but they’ve invited me to go along and play, so I’ll go and do that as well.

“I’ll come back and probably have a week off then probably go to York because it’s the UK Championships and I like York. Then off to Macau again at Christmas. That’s the plan.”

Among some of O’Sullivan’s best results this year have been runs to the semi-finals at the Shanghai Masters and the Xi’an Grand Prix.