Roethlisberger was limited in practice this week as he continues to come back from a sprained left knee suffered against St. Louis last month. Landry Jones is expected to make his first NFL start against the Chiefs (1-4). Jones threw two second-half touchdown passes to Martavis Bryant last week in a home victory over Arizona.
Murphy made the team out of training camp as an undrafted free agent out of Boston College before moving to the practice squad. He will serve as the backup behind Jones.
To make room for Murphy on the roster, the Steelers placed cornerback Cortez Allen on injured reserve with a knee injury.
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