The Colts' initial concern for Brown was his shoulder following one series of play against the Bears, but it was an elbow injury to the same arm that brough his season to a halt.
"It's more the elbow than the shoulder," head coach Tony Dungy said.
Brown's injury elevates young quarterback Tom Arth to the third-string spot following an exciting series where he moved the team nicely in the closing minute last week against the Bears.
"He'll get some work in the next two games," Dungy said.
The Colts used the roster spot created by Brown's injury to sign a former Colt Jim Newton, who played for Indianapolis in 2003 and was in their training camp last summer. Newton was recently waived by the Cardinals.
Travis Brown Placed on IR, Newton signed
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