ALLEN PARK, Mich. -- It started with a bad throw, a good catch and a perfect photo by the Detroit Lions' senior manager of digital media.
Glover Quin started to explain his interception of Ben Roethlisberger last Sunday when he stopped the conversation and yelled over to Stuart Zaas, the aforementioned senior manager of digital media.
"Stu, come here real quick," Quin said. "This one's funny. Every Friday, what do you do for us at practice?"
Zaas takes photos at every practice, and this season, he started snapping pictures of defensive backs on Fridays doing a drill where safeties line up in the corner of the end zone, next to a pylon, and practice catching the ball while keeping both feet inbounds.
Typically, Lions safeties coach Alan Williams had thrown the ball to Quin right in the basket he made with his hands in the corner of the end zone. One Friday early this season, though, Williams made an errant throw. Quin had to stretch to make the catch and keep his feet in.
Zaas snapped the picture. Showed it to Quin. The drill Williams and Quin had been doing was altered because Quin now wanted Williams to make slightly errant throws on purpose in order to challenge the Lions safety.
"When we started doing our ball drills and stuff, I used to kind of make a joke with our DB coach," Quin said. "He used to throw it, he used to throw it just accurately because I'd be standing like this so he'd try to throw it and hit the pocket. Then he started throwing some where I had to try and make a catch.
"I would always tell him, you know, you don't really make bad throws when you have a good receiver so I try to catch all of them that they throw. So he'll be throwing them way out there and I'll still reach. Every Friday."
And every Friday, Zaas has been taking photos of the drill, creating a progression of pictures. The practice led to Quin's interception Sunday -- one he called easier than the drill because he didn't have to worry about keeping his feet inbounds. Quin showed a picture of the interception. Then he showed one from one of the Friday drills.
The positioning of Quin's body was almost identical to what Zaas had shot in practice.
"Stu captured the moment and so it allowed me to talk about it to [Williams] so we continued to make those type of throws," Quin said. "So [if] Stu never captured that moment, who knows what would have happened on Sunday."
Quin insists he would have made the interception anyway -- and realistically, with the way Roethlisberger threw the ball, he would have had a good shot at it no matter what.
It ended up being the 24th interception of his career -- No. 19 with the Lions. The story also took Quin on a trip down interception memory lane.
His easiest interception came in his first game in Detroit against the Vikings -- a pick on a tipped pass that helped seal the game. The most difficult ended up being a tie between one against Peyton Manning two years ago on "Sunday Night Football" and one against the Buccaneers in 2014.
His favorites? Asking that caused Quin to give out an elongated "Eeeee" as he thought. Then he decided on one from this season against Matt Ryan and one from 2014 against Drew Brees.
Not all of them have come because of the Friday drill -- but almost all have been a product of some sort of extra work by Quin, who is meticulous in his film study and preparation. It allows him to read the offense before the snap -- something he did on his interception on Roethlisberger -- and has added anticipation for where a ball might go.
And that makes a difference.
"He does, I think, a really good job of recognizing concepts as they develop and then getting himself in position to make plays from there," Lions coach Jim Caldwell said. "Through the years he's been very good at that.
"There's been some pretty prolific safeties in this league that have done a pretty nice job in some of those areas and probably Ed Reed comes to mind as one that was extraordinary at that kind of thing, but Glover does a tremendous job."