Australia's Nick Kyrgios retired injured from his opening match at Queen's Club, just two weeks before the start of Wimbledon.
The 22-year-old, who has struggled with hip and shoulder injuries this year, slipped awkwardly at 4-4 in the first set of his match against Donald Young.
Ninth seed Kyrgios lay on court for a few minutes and had lengthy treatment on the sideline before resuming.
But, after squandering two set points, he quit after losing a tie-break.
More to follow.