Germany captain Michael Ballack is an injury doubt for Wednesday's World Cup qualifier against Wales after sitting out training Monday.

The Chelsea midfielder picked up a knock to his right calf during Saturday's Group Four win over Russia.

A statement on the German FA website read: ''While 18 players trained in the stadium, Ballack was treated in the team hotel by DFB physiotherapist Klaus Eder.

''The 32-year-old midfielder told coach Joachim Low at lunchtime about his knock.''

The German FA have stated Ballack did not take part in training ''as a precaution''.

Ballack scored the second goal in Germany's 2-1 win at the weekend which kept them top of the group.