A video tribute to the 40 passengers and crew members who were aboard the United Airlines Flight 93 that crashed into a field in Shanksville, Pa., was presented on the stadium scoreboard. During the presentation, 33 family members of the Flight 93 victims -- all of them holding American flags -- lined up along the infield dirt between first base and third base.
The Pirates and Brewers staff also watched silently from outside their dugouts.
"It's a tough moment for a lot of people out there," said Pirates shortstop Jack Wilson. "It's a tribute to those people who were heroes. To have their families out there in remembrance of them was very important. It's very important to have a chance to recognize them.
"You can't even fathom the type of emotions the families have had going through them the last five years, every day knowing that they lost someone over terrorism. Losing anyone is hard enough. It's hard to find the words to say."
A 60-by-90-foot American flag that was sewn together by high school students and donated to the Flight 93 National Memorial was unfurled in center field by members of the United States Armed Forces.
The Pirates also requested a moment of silence in memory of late Pittsburgh mayor Bob O'Connor, who passed away on Sept. 1, and those who died in battle during Operation Enduring Freedom and Operation Iraqi Freedom.
O'Connor's son, Corey, threw out the ceremonial first pitch.
"Sept. 11, 2001, is a day that none of us will ever forget," said Pirates CEO and managing general partner Kevin McClatchy in a statement released by the team. "It is important that we remember and pay tribute to all those who lost their lives that tragic day. The people aboard Flight 93 were true heroes. They gave their lives so that others would not be taken. We are honored to host so many of their family members at PNC Park on this anniversary date."
Ed Eagle is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.