Switzerland striker Blaise Nkufo was ruled out of the European Championship on Tuesday with a thigh injury.
The 32-year-old forward saw doctors Tuesday at the Swiss team's training camp to examine what was thought to be a torn adductor muscle, which requires several weeks of treatment.
Nkufo, who scored 22 goals this season for FC Twente as it qualified for the Champions League, was replaced by Thomas Haeberli in coach Koebi Kuhn's 26-man provisional squad.
Haeberli scored 18 goals this season for Young Boys but has only one international match in his career. The 34-year-old forward played the final 15 minutes of Switzerland's 6-0 victory over the Faeroe Islands in 2004.
Kuhn must name his final roster of 23 players by May 28.
On Monday, third-choice goalkeeper Fabio Coltorti was ruled out with post-viral fatigue, and was replaced with 23-year-old Eldin Jakupovic of Grasshoppers.
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