Yankees will retire Paul O'Neill's No. 21 jersey in August at Yankee Stadium's Monument Park
Yankees Are The Best Ever Fanpage
New York Yankees - Wikipedia
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Aaron Judge hits 200th career homer vs. Royals
Other retired number plaques are available. Mickey Mantle, Thurman Munson, Joe DiMaggio,Lou Gehrig, Phil Rizzuto, Babe Ruth, Yogi Berra, and Marino
Don Mattingly Old YANKEE STADIUM Monument Park Retired Number Plaque with Brick
Paul O'Neill takes in 'biggest dream' of his life as Yankees retire No. 21
DON MATTINGLY: FAME SECOND TO FAITH AND FAMILY
A tour of the new Yankee Stadium that could have been - Pinstripe Alley
Monument Park (Yankee Stadium) - Wikipedia