The Swiss team at next month's athletics world championships in Edmonton could be reduced to just five members, with 1,500 metres runner Sabine Fischer facing a late fitness test on her injured left foot.
Fischer had been suffering pain recently, and on Monday was only able to finish her Grand Prix race in Nice with a moderate time of 4'11"05. A subsequent examination has now revealed a stress fracture.
The St Gallen runner exceeded all expectations by reaching the 1,500 metres final at last year's Sydney Olympics, but may not now get the opportunity to build on that performance.
She will now undergo intensive treatment on the foot, before deciding whether she will take part in next week's Golden League meeting in Monte Carlo.
Depending on her progress and after further medical tests, Fischer expects to make a final decision about Edmonton on July 23.
The Swiss squad are already having to do without the injured Marcel Schelbert and the out of form Anita Weyermann.
Andre Bucher (800 metres) will spearhead the Swiss bid in Edmonton, after setting the world's best time this season on no less than three occasions. Peter Philipp, Alain Rohr, Christian Belz and Anita Brägger are the remaining members of the squad.
swissinfo with agencies