While the problem has not yet been diagnosed, Bjorn claims it felt like the shoulder popped out of its socket.
He first noticed some pain during his second round on Friday, and when it continued into the weekend, the Danish star decided to sit it out.
It hurts everytime I hit a shot, he said. Hopefully, it is not going to cost me the Ryder Cup.
With just three weeks left until the showdown at The Belfry, Bjorn is now doubtful to play the WGC American Express Championship and may not compete in the Trophee Lancome.
As he finished second on the European points list, he would be gravely missed in England.
Bjorns trainer Peter Richardson remained optimistic, however, believing the injury is rather a sublaxation of the shoulder, rather than a dislocation, whereby the damage is less severe.
European Ryder Cup captain Sam Torrance has taken notice of the situation as well, and while he remains in good spirits, he plans to contact Ian Poulter as a possible replacement should Bjorn remain out for an extended period.
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