Jonathan Gannon knew it was over.

And he was shattered.

The pride of Saint Ignatius High School in Cleveland, who had dreams to one day suit up in the NFL, was forced to abandon those dreams in the spring of 2004.

Bobby Petrino, then the head coach at Louisville, still remembers sitting in his office in Papa John’s Cardinal Stadium when a 21-year-old Gannon came to deliver the news.

“It was emotional. There’s no question about it,” Petrino said to NBC Sports Philadelphia this week.

“It was really hard on him. … There were certainly tears shed. Something that he had been doing since he was a young kid had just been taken away from him.”

During that tearful meeting an idea was hatched that eventually set Gannon on a path to achieve great things in the world of coaching. This offseason, that path has taken Gannon to Philadelphia as the Eagles’ new defensive coordinator under head coach Nick Sirianni.

This is the story of how Gannon turned disaster into triumph and how an unusual start to his coaching career has catapulted him to the highest level.

Smooth as White Chocolate

To understand how much Gannon was giving up when a devastating hip injury and surgery forced him to stop playing, you have to first realize how good he was to begin with.

“JG was a baller,” said Gannon’s Louisville teammate Antoine Harris.

That began at Saint Ignatius. Legendary Wildcats head coach Chuck Kyle has seen a lot of great players come and go in his nearly four decades and Gannon was just one of those guys.

You know, the special ones.

Gannon earned a scholarship to Louisville after he was a two-year starter as a defensive back and receiver in high school. But it wasn’t just football. He also starred in basketball and track and field. Kyle remembers sitting in front of Gannon’s parents at the state championship basketball game in 2001. The Wildcats were up one point with about 12 seconds left to go and as Gannon was bringing the ball up, he was fouled by an Elder High School player, putting him on the line with the game hanging in the balance.

“You know they fouled the wrong guy, don’t you?” said Kyle, neck craned, to Gannon’s parents.

Gannon drilled both free throws. Saint Ignatius won 49-46, clinching the only basketball championship in school history. He then competed in track and field that spring and helped the school clinch its first state championship in that sport as well.

“Jon was a three-sport guy here at St. Ignatius High School,” Kyle said. “Could have been four-sport, but with the calendar, you can only do three.”

When Gannon arrived at Louisville, his new teammates were similarly impressed by his athleticism on and off the football field. When they would go to the gym to play basketball, Harris remembers Gannon rising up and dunking.

Harris and fellow Louisville teammate Kerry Rhodes, who both played in the NFL, think Gannon would have eventually played in the league too.

Gannon was just a smooth guy back then. Rhodes joked that he and Gannon considered themselves good-looking ladies men and would often compete for the attention of young women. But Gannon was smooth on the football field too. Upon his arrival at Louisville, his new teammates took notice. Around this time, Jason Sehorn was one of very few white defensive backs in the NFL, so Gannon earned a new nickname.

“I did call him White Chocolate,” Rhodes said. “He’s just such a cool dude. He was fast, strong, athletic, all those things. And it’s like, ‘Who is this dude? Where did he come from? Oh, that’s White Chocolate. That’s his name. That’s him.’”

And White Chocolate was destined for big things. Gannon red-shirted in 2001 but was named the Cardinals’ Defensive Scout Team Player of the Year. In 2002, he began the season as a backup until the ninth game of the season, when he got the first start of his collegiate career.

That’s when everything went wrong.

The injury

The Cardinals lost to the Bearcats 24-14 on Nov. 7, 2002, but Gannon lost more that day. According to a 2004 Louisville media guide, that’s when Gannon suffered a catastrophic hip injury that needed surgery, ending his season and, eventually, his football career.

“It was just one of those freak injuries,” said Rhodes, who got to Louisville one year before Gannon. “He was running, planted and his hip just gave out.”

Petrino and former Louisville kicker Art Carmody (in this 2011 article) have compared Gannon’s injury to that of Bo Jackson. In 1991, Jackson suffered a hip injury that ended his NFL career. It’s one of the most notorious injuries in sports history.

Gannon’s original plan wasn’t to go into coaching. He spent 2003 rehabbing and trying to get back on the football field. To his credit, he did. When Petrino was hired by Louisville to replace John L. Smith in 2003, he heard about a talented young safety who was working his way back.

In 2004, Gannon was back on the field during spring practices, but his hip just wasn’t right. Petrino remembers there would be glimpses of the player Gannon once was but the pain had become unbearable. Gannon would look great one day and then struggle for three or four days to recover.

“Seeing him go through that was really tough for me,” Rhodes said. “It also made me cherish the time that I had on the field because we don’t know when our time is up when it comes to that stuff. Freak things happen all the time.

“To see it happen to such a good person and to see him have to struggle with it at first and then come to grips with it, that, ‘This isn’t for me anymore. Now, what do I do? Do I sit around and mope about it, do I sit around and complain? Or do I do something positive to make this thing worthwhile?’ And that’s what he did, that’s what he’s about.”

His start in coaching

That brings us back to that meeting in Petrino’s office in 2004. Gannon’s playing career was over so — after they made sure he could stay on scholarship — a plan was hatched to make Gannon a volunteer student coach.

He was a natural.

“To me, it was amazing how much respect the players had for him, first and foremost,” said Petrino, now the head coach at Missouri State. “How well he did communicating, the energy he showed for it. I’ve been around a number of guys, the first time you watch them, the first time you see them, you say this guy’s got something special about him. There’s no question Jonathan had something special about him as far as communication and teaching and motivating.”

Gannon began coaching that spring and stuck around that summer, continuing to work with his former teammates. He spent three seasons as a volunteer assistant and one as a graduate assistant at Louisville.

You might think it would have been weird for Gannon to go from teammate to coach, but it wasn’t. His teammates already respected him and were happy to listen to whatever he had to say.

“He was like Coach Gannon out there,” Harris said. “He had his paper tucked into his shorts like all the coaches. He had his coach’s hat on. He was out there literally keeping us together.”

In those early days, Gannon’s responsibilities included game-planning and providing scouting reports on upcoming opponents, but he also coached his former teammates on the field. Rhodes remembers how helpful it was for him to have another set of eyes he trusted. Gannon was a natural at spotting tendencies from opponents and had the knack for communicating that information to his players successfully.

Gannon did such a good job that when Petrino was hired as the Atlanta Falcons’ head coach in 2007, he brought Gannon with him.

His rise in the NFL

Petrino gave Gannon his first job in the NFL as a defensive assistant and quality control coach. Those early days he did pretty much the same things for the Falcons that he did while still at Louisville.

Gannon was also reunited with Harris in Atlanta. Harris went undrafted in 2005 and after a couple of seasons in Tennessee, where he didn’t see the field, he joined the Falcons in 2007. Harris said Gannon was still the same guy.

“He’s a realistic guy as far as when he teaches you something, he’s not teaching you from a blanket perspective,” Harris said. “He’s tailoring it to the individual player.”

After a brief foray into scouting, Gannon returned coaching as a quality control coach for the Titans from 2012-13. He then became the assistant defensive backs coach in Minnesota for four years and was the Colts’ defensive backs coach for the last three.

As Rhodes said, everything Gannon does is “intentional.” NFL players want a coach who is prepared, who treats them like men, who can relate to them and who can show them that he’ll make them better. Gannon seems to check every box.

“One of the things that’s impressive about him is the people around him, I’ve never heard anybody say a bad word around him,” Petrino said. “Not as a person or a coach or a player, anything.”

Gannon was a very good football player but coaching just seems to fit him. His former teammates think that even if he had a longer football career as a player, he would have eventually gotten into coaching. His horrific injury 19 years ago just sped up that process.

Kyle, Gannon’s high school coach, wrote a book in 1997 called, “The Object of the Game.“ It’s a book about coaching, but it’s not about X’s and O’s; instead it has chapters with titles like Discipline, Commitment, Preparation and Leadership.

A few months ago, Gannon texted Kyle to tell him that he reread the book and even used some of its teachings with his players in Indianapolis.

Gannon will now bring his copy of the book with him to Philadelphia. He’s always been a coach. It just took a setback to find out.

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