Frei, who spent most of last season nursing his knee, left the pitch in tears before the break on Saturday, following a collision with Zdenek Grygera.

MRI scans ensured that Switzerland's all-time leading goalscorer will play no part until the end of the competition.

"The injury is a shock, no doubt about it, to lose our skipper is a disaster," said Swiss coach Jacob Kuhn.

After losing 1-0 to the Czechs, Switzerland take on Turkey on Wednesday.