San Francisco 49ers linebacker Chris Borland, center, during an NFL football game in Santa Clara, Calif. Borland announced that he will retire after just one season to protect himself from brain injuries. Marcio Jose Sanchez/AP hide caption

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Syracuse coach Jim Boeheim, right, speaks with an official during the first half of an NCAA college basketball game against Duke in Durham, N.C., on Feb. 28 Gerry Broome/AP hide caption

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Daina Bouquin competes in the first U.S. Winter Swimming Championships on Saturday in Lake Memphremagog near Newport, Vt. The event drew swimmers from around the world to race in icy water that was below 32 degrees F. Herb Swanson for NPR hide caption

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A man watches sports broadcast on screens at a sports book owned and operated by CG Technology in Las Vegas. CG Technology is asking the Nevada Gaming Control Board to allow betting on the Olympics. John Locher/AP hide caption

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Panelist Nahshon Ellerbe, a star running back at Trinity Christian Academy in Addison, Texas, warms up before a game against Midland Christian. Jeffrey McWhorter/Trinity Christian Academy hide caption

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A sculpture at Britannia stadium in the English city of Stoke-on-Trent commemorates the Christmas Truce, a legendary soccer game played between German and British troops in December 1914. Rui Vieira/AP hide caption

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Members of the St. Louis Rams raise their arms to protest the grand jury decision in Ferguson, Mo., before a game last month. The players faced a backlash from St. Louis police and have been asked to apologize. L.G. Patterson/AP hide caption

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Baltimore Ravens fans exchange the jersey of the team's former running back Ray Rice at M&T Bank Stadium Friday. "He should have been the man here and backed away" instead of hitting his fiancee, a female fan says. Patrick Smith/Getty Images hide caption

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Former St. Louis Cardinals manager Tony La Russa is introduced before Game One of the World Series in 2011. La Russa will be inducted into the Baseball Hall of Fame on Sunday. Paul Sancya/AP hide caption

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