Yoan Francisco, a rookie for the Havana Industriales, warms up before a game at Havana's Latin American Stadium. Cuban baseball has been facing hard times, but improved diplomatic relations with the U.S. have raised the possibility of increased cooperation and new opportunities. Eyder Peralta/NPR hide caption

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At this stage in the election cycle, just like in baseball's spring training, fans love to see a new phenom catch fire. Wisconsin Gov. Scott Walker, sporting a Milwaukee Brewers jersey in 2013, seems to be the rookie to watch in the 2016 presidential race so far. Manuel Balce Ceneta/AP hide caption

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Game clocks will be a common, and mandatory, sight at MLB stadiums in the 2015 season. But they'll only be used between innings, unlike pitch clocks like this one at an Arizona Fall League game. Mike Janes/Four Seam Images via AP hide caption

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San Francisco Giants manager Bruce Bochy (right) had two heart stents inserted Thursday. He's seen here during the Giants' World Series victory parade last year. Jason O. Watson/Getty Images hide caption

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In this Aug. 27 photo, members of the Jackie Robinson West Little League baseball team participate in a rally in Chicago celebrating the team's U.S. Little League Championship. Little League International has stripped the team of its national title after finding the team falsified its boundary map. Charles Rex Arbogast/AP hide caption

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When the Giants' Gregor Blanco hit this solo home run to lead off the World Series' second game, three big parabolic microphones arranged around home plate captured the crack of his bat. Elsa/Getty Images hide caption

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Mike Trout and Los Angeles Angels have been named favorites to reach the World Series, as have Clayton Kershaw and the Los Angeles Dodgers. They're seen here when the two teams played in August. Matt Brown/Angels Baseball LP/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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Horace Wilson and other members of his family in a portrait believed to date to the 1860s. He's the mustachioed fellow standing at top right. Courtesy of Abigail Sanborn hide caption

itoggle caption Courtesy of Abigail Sanborn

Retired baseball pitcher Tommy John, left, and Dr. Frank Jobe at the National Baseball Hall of Fame in July 2013. Jobe was honored for the pioneering surgery he first performed on John's elbow in 1974. Mike Groll/AP hide caption

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