Trae Turner of the Washington Nationals and Atlanta Braves pitcher Mike Foltynewicz watch the flight of the ball on Turner's first-inning home run at Nationals Park in Washington, D.C., June 12, 2017. The Braves won, 11-10. (Joe Gromelski/Stars and Stripes)

The Washington Nationals' president mascots, clad in appropriate uniforms for the occasion, on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Washington Nationals outfielder Bryce Harper cools off between innings of a game against the Atlanta Braves at Nationals Park in Washington, D.C., June 12, 2017. The temperature at game time was 91 degrees. (Joe Gromelski/Stars and Stripes)

A fan shows off his foul-ball souvenir on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Acting Secretary of the Army Robert M. Speer throws out the ceremonial first pitch on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

The color guard is dressed in World War I uniforms on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Maj. Gen. Timothy M. McKeithen, Deputy Director of the Army National Guard, salutes during the national anthem on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

The U.S. Army Old Guard Fife and Drum Corps performs on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Soldiers from the 1st and the 4th Battalions of the 3rd Infantry Regiment walk onto the field on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Acting Secretary of the Army Robert M. Speer poses for a photo with soldiers' children on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Acting Secretary of the Army Robert M. Speer talks with soldiers' children on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Washington Nationals mascot Screech talks with members of the Army Chorus of The United States Army Band on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Acting Secretary of the Army Robert M. Speer talks with members of the Army Chorus of The United States Army Band on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

A young fan enjoys U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

The Army Chorus of The United States Army Band prepares to perform the National Anthem on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Washington Nationals mascot Screech talks with soldiers' children on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Acting Secretary of the Army Robert M. Speer, right, talks with Maj. Gen. Timothy M. McKeithen, left, Deputy Director of the Army National Guard and Lt. Gen. Aundre F. Piggee, Deputy Chief of Staff, G4 (Army Logistics), on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

The U.S. Army Drill Team performs in center field on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

The U.S. Army Drill Team prepares to perform in center field before the game between the Washington Nationals and Atlanta Braves on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)

Manager Dusty Baker and the Washington Nationals are joined on the field by soldiers from the 1st and the 4th Battalions of the 3rd Infantry Regiment for the singing of the national anthem on U.S. Army Day at Nationals Park in Washington, D.C., June 12, 2017. (Joe Gromelski/Stars and Stripes)