Former U.S. President George H.W. Bush (R) watches as his son, former President George W. Bush, throws a ceremonial first pitch prior to the start of Game 4 of Major League Baseball's World Series between the San Francisco Giants and the Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL IMAGES OF THE DAY) 

Former U.S. first lady Laura Bush waves a towel beside former U.S. President George W. Bush as Texas Rangers' Nelson Cruz (L) stands on deck during the fourth inning of Game 4 of Major League Baseball's World Series between the San Francisco Giants and Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL) 

Former U.S. President George H.W. Bush does the Texas Rangers' deer horn gesture during Game 4 of Major League Baseball's World Series against the San Francisco Giants, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL HEADSHOT) 

Former U.S. President George H.W. Bush (R) watches as his son, former President George W. Bush, throws a ceremonial first pitch prior to the start of Game 4 of Major League Baseball's World Series between the San Francisco Giants and the Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL) 

Former U.S. Presidents George H.W. Bush (C) and George W. Bush chat with Texas Rangers president Nolan Ryan (R) prior to throwing of the ceremonial first pitch before the start of Game 4 of Major League Baseball's World Series between the San Francisco Giants and the Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL) 

Former U.S. presidents George H.W. Bush (R) and George W. Bush stand with Texas Rangers president Nolan Ryan (C) prior to the throwing of the ceremonial first pitch before the start of Game 4 of Major League Baseball's World Series between the San Francisco Giants and the Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL) 

Former U.S. presidents George H.W. Bush (L) and George W. Bush ride in a golf cart prior to the start of Game 4 of Major League Baseball's World Series between the San Francisco Giants and the Texas Rangers, in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL) 

Texas Rangers fans wearing George W. and Laura Bush masks wait for the start of Game 4 of Major League Baseball's World Series between the Rangers and the San Francisco Giants in Arlington, Texas, October 31, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL POLITICS) 

Former U.S. President George W. Bush (L) and Texas Rangers President Nolan Ryan (R) stand as Texas Rangers' Mitch Moreland warms up in the seventh inning during Game 3 of Major League Baseball's World Series against the San Francisco Giants in Arlington, Texas October 30, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL IMAGES OF THE DAY) 

Former U.S. President George W. Bush (L-R), wife Laura and Texas Rangers President Nolan Ryan watch during Game 3 of Major League Baseball's World Series between the Rangers and the San Francisco Giants in Arlington, Texas October 30, 2010. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT BASEBALL POLITICS)