When the measure was announced by Commissioner Bud Selig in January 2003, and subsequently approved by the Major League Baseball Players Association, Selig said the change was implemented to add meaning to the All-Star Game.
The American League, which hasn't lost an All-Star Game since 1996, has had the home-field edge each of the last four years as a result of victories in the Midsummer Classic, and yet how much of an impact it has had in the World Series is debatable since the two leagues have split the four Fall Classics played since the All-Star Game outcome factor was implemented.
In 2003, the National League champion Marlins defeated the Yankees in the World Series, 4-2. The Marlins split the first two games at Yankee Stadium, won two of three at home and then clinched in Game 6 back at Yankee Stadium.
In 2004, Boston had home-field advantage and swept St. Louis, 4-0, winning two at Fenway Park and two at old Busch Stadium. The next year the White Sox, also with home-field advantage, swept Houston, winning two at U.S. Cellular Field and two at Minute Maid Park.
Last year, the Cardinals opened the World Series at Detroit, where they split a pair at Comerica Park before returning to new Busch Stadium to complete their series victory in five games.
A four-year sample is, at best, anecdotal evidence, but so far the teams with the home-team advantage have won two World Series and lost two. During that same period, the home-field advantage enjoyed by the American League has meant a 6-3 record in World Series games played in their home parks. All home teams in World Series play over the last four years are a combined 11-8.
The AL has won 10 of the last 15 World Series and has dominated Interleague Play for the last four years. The Junior Circuit posted a 137-115 record against the NL in Interleague Play this season.
Jim Molony is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.