Jon Dorenbos played a little chess with friends in high school when he wasn't lettering in football, baseball and basketball.
And he played in college when he wasn't honing the long-snapper technique that landed him a spot with the Eagles.
"I've got some skills on the board," he crowed as he turned from autographing jerseys and faced his opponent, Christian Trinidad, age 11.
The kid put him in check in four moves.
"He knows what I'm doing," the lineman complained, index finger pressed to his temple, as Trinidad quickly eliminated the Eagle's most valuable pieces - first a bishop, then a rook, then his queen.
In eight minutes it all was over.
The small assassin smiled, and his coach, Cyrus Knower, chess coach for the Community Academy of Philadelphia, slapped him on the back.
"It's OK," the coach consoled the NFL player. "He's in fifth grade."
And he's not just any fifth grader.
Dorenbos was beaten by the best fifth-grade chess player in the Philadelphia School District, according to tournament organizer Steve Shutt, a teacher at Masterman.
"I don't know what happened," shrugged Dorenbos, a goateed and sculpted 26-year-old who works as a professional magician on the side. Unfortunately, he could not make his opponent's pieces disappear.
"I haven't been beaten like that since freshman football in high school."
Trinidad was one of four competitive chess players in his family to travel from Nicetown to Lincoln Financial Field Thursday to vie for trophies in the gleaming halls of a pro arena.
David Trinidad, at 17 the oldest, said each child learned the game in the After School Activities Partnerships program, which since 2004 has created 210 chess clubs around the city.
"They're well on their way to creating a chess dynasty," Marciene Mattleman, director of the after-school program, said of the Philippine-born Trinidads. The family - dad's a pastor, mom's a nursing aide - is carless, so after a friend drove them as far as Harrisburg for a recent state championship, their parents hired a cab to take them on to Carlisle.
The Eagles organization got the chess program started with a $10,000 grant. Sarah Martinez-Helfman, executive director of the team's Youth Partnership, said the Eagles made the stadium available to show talented players from tough neighborhoods "that we're cheering for you."
Mattleman says research shows that chess teaches conflict-resolution skills. Those are useful in the parts of the city the program serves between 3 and 6 p.m., a dangerous period of the day because so many teens are unsupervised.
"Principals tell us that because of chess, kids see the consequences of their actions and they don't get involved in risky behaviors. Kids develop patience, not just acting in the moment. Kids learn to win and lose with grace and courtesy."
John Kan, 13, said the game keeps his mind from the gunshots.
The South Philly teen had just finished the first match of the day. He'd sat with a former schoolmate at Southwark Elementary at the end of three banquet tables set with timers and boards. Depending on the players' levels of skill, the games were to take 60 or 80 minutes.
Kan won in three minutes.
Ray Smith, Southwark's math teacher and chess coach, didn't know Kan could even play until three months ago, when the boy showed up at chess club and destroyed him three times in a row. He'd learned from friends on the street.
"The game helps you think about the sacrifices you should make - like, what would you lose in order to take someone's bishop?" reflected Kan, an eighth grader from Cambodia who also shines on the basketball court and in math class.
His coach added, "We're on Ninth Street in South Philly, and there are gangs on either side of the school. It takes conflict resolution just to get here."