British doubles number one Colin Fleming looks set to miss the French Open and is a doubt for Wimbledon after being ruled out for at least six weeks.
The Scot revealed on Wednesday he was facing "six to eight weeks" on the sidelines due to a stress fracture of his left tibia.
Fleming tweeted: "Bad news folks. I've withdrawn from the tournament here (in Monte Carlo) with an injury.
"Focused on rehab now and hoping to be back on court in six to eight weeks.
"Going to do all I can to minimise the time I'm out injured. Aiming for 6 weeks not 8."
It is already less than six weeks before the French Open gets under way. The event begins on May 27.
An eight-week lay-off takes in the AEGON Championships at Queen's Club. Wimbledon starts on June 25.
Fleming, ranked the 25th best doubles player in the world, has formed an impressive partnership with fellow Briton Ross Hutchins in recent times.
They won their first ATP title together in St Petersburg at the end of last season and triumphed in Delray Beach earlier this year.
Fleming's injury is also a major blow to the pair's hopes of securing a place in the season-ending Barclays ATP World Tour Finals in London - a stated aim of theirs in the winter.
However, with just 190 ranking points to defend before the June 11 cut-off point for the Olympics, Fleming should still qualify to compete in this summer's Games in London.