Switzerland coach Kobi Kuhn is sweating on the fitness of three key players ahead of his side's World Cup opener against France on June 13.

The main doubt is midfielder Valon Behrami, who is making slow progress in his recovery from a groin injury.

Arsenal central defender Philippe Senderos missed training earlier in the week because of a thigh strain, but the Swiss medical staff are optimistic he will be ready to mark his club team-mate Thierry Henry in the Group G clash in Stuttgart.

The other worry is attacking full-back Ludovic Magnin, who needed stitches in a facial wound following a training ground collision with Philipp Degen on Friday.