Two-time Olympic and world heptathlon champion Nafi Thiam is a doubt for the World Athletics Championships.
Thiam, 28, withdrew from the Belgium National Championships at the weekend because of an Achilles tendon problem.
The reigning champion is yet to confirm her entry for the championships in Budapest, which start on 19 August.
“It remains to be seen how her tendons will react to the upcoming intensive training sessions,” said Thiam’s coach Michael Van der Plaetsen.
“Tendonitis never comes at the right time. If you don’t slow down, things could get worse,” he added, speaking to Belgian newspaper Le Soir.
Thiam, who missed recent Diamond League meetings in Monaco and London, pulled out after two heptathlon events at her national championships.
She set a pentathlon world record at the European Indoor Athletics Championships in Istanbul in March, scoring 5,055 points.
A total of 6,947 points clinched her second heptathlon world title in Eugene last year, ahead of the Netherlands’ Anouk Vetter and American Anna Hall.
