Pete Alonso 9/11 Cleats New York Mets
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Saturday marks the 20th anniversary of 9/11, the deadliest terror attack on U.S. soil, and the New York Yankees and Mets players are paying respect to those who lost their lives and the first responders with their apparel. Yankees outfielder Aaron Judge, along with the Mets' Pete Alonso and Kevin Pillar, wore 9/11-inspired cleats during their game in Citi Field. 

Alonso's Nike cleats read "WE WILL NEVER FORGET" and showcase the American flag. Judge's cleats, which are made by New Balance, feature the Twin Towers on one side of the shoe and New York Fire Department firefighters raising an American flag on the other.  Pillar's Adidas cleats feature NYFD firefighters squatting on one side and the New York skyline on the other. 

As a team, the Mets are wearing 2001-style uniforms along with hats and helmets honoring the New York Police Department, NYFD and various other responding organizations for the game. 

While the Yankees aren't changing their uniforms -- aside from some wearing NYFD hats -- players have shared what 9/11 means to them while offering their thoughts and prayers. 

"I am proud to be in NY today, to be a part of remembering the lives lost and honoring our heroes," Yankees first baseman Anthony Rizzo wrote on Twitter. "May God bless the memories of those we lost and may he bless their loved ones who continue to live with the pain and loss. We will never forget." 

Yankees pitcher Jameson Taillon, who's playing his first season in New York, also shared his thoughts. 

"Thank you to the heroes who stepped up to help in the face of danger 20 years ago," Taillon wrote on Twitter. "Can't help but think of the families who were missing their loved ones for all of life's precious moments and milestones over the last 20 years. Thinking of everyone affected." 

Prior to the game, the Yankees and Mets players joined midfield to honor those who lost their lives or fought to save them during the 9/11 attacks. 

Saturday's game is the second of a three-game series between the Yankees (78-63) and Mets (71-71). The Mets handily won the first game, 10-3. They'll play the final game in Citi Field on Sunday at 8:08 ET on ESPN.