LOOK: Every last undefeated NFL team since the 17-0 Miami Dolphins
The Pittsburgh Steelers lost to Washington in Week 13. Here is a list of every last undefeated team from every season since the 1972 Miami Dolphins.
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Sports blog information from USA TODAY.
The Pittsburgh Steelers lost to Washington in Week 13. Here is a list of every last undefeated team from every season since the 1972 Miami Dolphins.