Bobby Valentine, John Franco, Al Leiter and Todd Zeile visited Engine 3, Ladder 12, Battalion 7 in Manhattan on Thursday.
The Mets have been honoring different fire companies each year since the attack.
For the former Mets, they were part of one of the most emotional nights ever in sports history. It was September 21, 2001, when baseball returned to New York for the first time since the catastrophe.
With the world watching, it was a night New Yorkers came together to honor the heroes of 9/11. It was a night when stars shined brightly.
For the first time, New Yorkers were allowed to smile again. It was a night that Mike Piazza produced one of the biggest moments in baseball history.
For many, a return to normal life happened at the moment Piazza hit the ball. It was a night that saw tears turned to cheers and the players have not forgotten.
"Obviously the 9/21 game and how that materialized to be almost scripted for this Mets team and the city of New York, it's great to commemorate this in a way like we're doing this weekend," Zeile said.
CLICK HERE for more Eyewitness News reflections, photos and stories marking the anniversary of 9/11
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