Sharp's second goal -- his fifth of the season -- came with 7:08 left and lifted the Hawks to their second win over the Sabres this week.
Chicago goalie Marty Turco stopped 38 shots in the victory.
Cody McCormick, Drew Stafford and Paul Gaustad all scored in the Sabres' fifth straight loss.
Patrick Lalime let in four goals on 21 shots for Buffalo.
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