Cory Undlin looked over at Avonte Maddox at practice last week and told him, hey, go play safety.
This is a 22-year-old rookie fourth-round corner who had never played a snap on defense and had never played safety in his life.
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"I got you," Maddox recalled. "That's what it was. No hesitation."
Maybe it's hard to call a player's debut at a new position a success when he allowed the game-winning touchdown in overtime, but Maddox's first NFL game as a defensive player actually was impressive.
With Rodney McLeod out for the season after undergoing knee surgery, Maddox became the Eagles' third safety, and he played 20 snaps in the Titans' 26-23 win over the Eagles Sunday in Nashville.
"It's challenging, but I'm up for anything," Maddox said. "It's fun. You come out here and you're able to learn more positions and learn more things on the field. It makes the game easier when you know what everyone's doing.
"I'm just doing whatever the guys need me to do. Any way I'm able to help, I'm willing to do it."
It was an up-and-down game for Maddox, who recorded his first interception in the second quarter, leading to an Eagles field goal, but also slipped in the end zone while covering Corey Davis on his game-winning touchdown.
"I think I did all right, other than the last play," he said. "Think I did all right for my first time."
He really did, which is kind of crazy considering his lack of experience, his lack of size and his lack of a background as a safety.
"He's got excellent quickness and great eyes for the football," defensive coordinator Jim Schwartz said of Maddox.
"He's got the combination of being able to cover and being able to play the run. All the things we liked about him as nickel, we also like about him as a safety. And I think we'll see more of him going forward in that role."
At 5-9, 184 pounds, Maddox does not have typical safety size. In fact, he's the shortest Eagles safety ever and the lightest since 178-pound Brenard Wilson, a starter on the 1980 Super Bowl team
He's also the shortest active safety in the league.
"It doesn't affect me," he said. "It's still football. Gotta be able to tackle, gotta be able to cover. In this defense you've got to be able to tackle at corner, at nickel and at safety. It doesn't matter."
There were a few ways the Eagles could have gone once they lost McLeod.
Rasul Douglas has safety size and skills. Jalen Mills could have moved, with Sidney Jones going from the slot outside and Maddox taking over in the slot. Tre Sullivan and Deiondre' Hall were options.
But Schwartz took an unconventional route in finding a third safety.
"Avonte is another guy that's very competitive," Schwartz said. "He's quick. He's really smart. We really like him as a player and that was a good chance for us to be able to get him on the field."
Maddox better be mentally tough to handle what he's about to face.
"You've got to be mentally tough no matter where you're playing or what year you're in," Maddox said. "But that's one thing I've always been, so any challenge they throw at me I'm willing to take it on."
This is quite a challenge for an inexperienced rookie, especially considering some of the quarterbacks the Eagles face the rest of the season – Kirk Cousins of the Vikings Sunday, Eli Manning, Dak Prescott and Alex Smith twice, Drew Brees, Cam Newton and Jared Goff later in the season.
It won't be easy. But if Maddox is what the Eagles think he is, that's one more impressive young DB in a stable of impressive young DBs that's only going to keep getting better.