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5 Oct 1998: Running back Robert Smith #26 of the Minnesota Vikings in action during a game against the Green Bay Packers at the Lambeau Field in Green Bay, Wisconsin. The Vikings defeated the Packers 37-24.

Odd and premature sports retirements

The Detroit Lions announced Tuesday that WR Calvin Johnson has retired. Johnson, who walks away at age 30, signed a 7-year contract extension in 2012 worth $113.5 million. Here's a look back at some other odd, abrupt or premature retirements by star athletes over the years.