Ronnie O'Sullivan has pulled out of the BetVictor Scottish Open citing medical reasons.The 48-year-old world number one, who earlier this month won a record-extending eighth UK Championship title in York, had been due to face Liam Graham in the opening round, but Graham will now receive a bye.O'Sullivan is a two-time winner of the Scottish Open, beating John Higgins in the 1998 final and seeing off Mark Williams two years later.He was runner-up to Mark Selby in 2020, losing the final 9-5.Although his 10-7 win over Ding Junhui in the UK Championship final made the seven-time world champion both the youngest and oldest ever winner of the competition, O'Sullivan has recently had issues away from the table.He withdrew from the Champion of Champions tournament in November, saying he was "mentally feeling a bit drained and stressed" after taking part at the International Championship in China.