Andy, Pettitte, Derek Jeter, Jorge Posada and Mariano Rivera are known as the New York Yankees' "Core Four", as they helped lead the way to a dynasty in the late-199s and early 2000s. Each of these players first donned the Yankees pinstripes in 1995 and went on to win four World Series championships by 2000. This baseball is autographed by all four of these Yankees legends and is sure to be one of your most prized pieces of memorabilia in your collection.