Andy Murray's recovery from hip surgery has run into difficulty, and it seems increasingly unlikely he will be able to make his comeback in Loughborough this month.
The double Wimbledon champion is not thought to have done very much at all on court in the past two weeks.
Murray, 30, has also pulled out of two corporate appearances.
The Scot has not played competitively since Wimbledon last year and had an operation on his right hip in January.
Publicly, he has been targeting the grass court season for a return to the tour. But privately there had been high hopes he would be able to play in the new ATP Challenger Tour event in Loughborough, which begins on 21 May.