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.
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Kurt Busch drives during the NASCAR Sprint Cup Series auto race in Fort Worth, Texas, on Nov. 2, 2014. Busch was recently suspended indefinitely amid domestic violence accusations.
Kentucky's Aaron Harrison and coach John Calipari watch from the sideline during the second half of an NCAA college basketball game against Mississippi on Jan. 6. Kentucky won 89-86 in overtime.
Tiger Woods on the ninth hole during the second round of the Phoenix Open last Friday, in Scottsdale, Ariz. Woods, who'll turn 40 this year, is making Frank Deford wonder: How does an athlete know when to retire?
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.
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.
Alabama defensive back Nick Perry (right) breaks up a pass on Auburn wide receiver D'haquille Williams (center) as Alabama defensive back Landon Collins looks on during the second half of the Iron Bowl NCAA college football game Saturday in Tuscaloosa. Alabama won 55-44.
The executive committee of FIFA — the international organization that regulates soccer — was so suspected of taking bribes that FIFA ordered its own internal investigation. It's no surprise, says Frank Deford, that it found no wrongdoing.
Kirill Kudryavstev/AFP/Getty Images