Kyle Edmund has called time on his 2018 campaign after a scan showed a small amount of fluid behind his left knee.
The injury is not regarded as serious but Edmund has pulled out of the Paris Masters this week.
The 23-year-old recently captured his first ATP Tour title, when he beat Gael Monfils in the Antwerp final.
That result capped a fine 2018 for Edmund, who is currently No 15 in the ATP World Rankings.
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October 30, 2018, 10:00am
Home hope Richard Gasquet has made a winning start to his Paris campaign, punishing an erratic display from Canadian teenager Denis Shapovalov and progressing to the second round with a 6-4 7-6 victory.
Powerful Russian Karen Khachanov began his campaign with a 7-5 6-2 win over last year’s runner-up Filip Krajinovic.