Sgt. Justin Callahan, a retired Army soldier who lost a leg in Afghanistan, threw out a first pitch before the game. Callahan represented Hire Heroes USA, an organization that attempts to find job placement for returning military veterans who sustained disabilities in combat.
The club welcomed members of the armed services, police men and women and fire fighters, and held a moment of silent remembrance for those who lost their lives in the attacks.
The Cardinals and Cubs, along with teams throughout baseball, donned special caps for the occasion, like those they wore on July 4 -- with a stars-and-stripes color pattern inside the team logo.
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.