Snipers patrolled the roof behind the bleachers in right-centerfield. Helicopters hovered above the stadium before the game. Metal detectors were used to screen well-heeled fans entering the pricey Legends Suite Club and again outside seats on the first level of the stadium.
Regular fans were allowed in with the normal pat-down and check of purses and cell phones. The Secret Service wasn't much of a secret - there was a visible presence on the field and in the stands and concourses.
Major League Baseball dedicated last night's game to the charity Welcome Back Veterans.
Obama and Biden emerged from a tunnel near the third-base dugout 10 minutes before game time and braved icy winds to escort World War II veteran Yogi Berra - the Yankee Hall of Fame catcher - to the mound for the first-pitch ceremony.
All three were wearing jackets with "World Series" on the front and their names on the back.
Iraq war veteran Tony Odierno threw the first pitch to Yankees captain Derek Jeter, to a big ovation. Odierno, who lost his left arm in the Iraq war, works in the Yankees' stadium operations department. His father is Gen. Raymond Odierno, the top U.S. commander in Iraq.
The national anthem was performed by retired Army Ranger Keni Thomas. A giant American flag was unfurled in centerfield during the moving performance.
Biden is a Phillies fan. Obama, unlike her White Sox-fan husband, grew up a Cubs fan. Obama -- and Biden -- got a kiss from Jeter on their way off the field, with Obama giving fans a high-five as she walked back down the tunnel.
The New York Police Department would not comment on the number of additional officers on hand last night.
Secret Service spokesman Darrin Blackford was even more vague, saying, "We will not confirm or deny information about the first family's schedule."
With Zachary Dowdy
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