AMES, Iowa -- Iowa State's Jacob Gannon is like a lot of seniors preparing for their final games this weekend: nostalgic, reflective, grateful.
During Senior Day last week, Gannon recalled all the memories he had at Jack Trice Stadium, including the team's upset of No. 2 Oklahoma State in 2011, when he started his second game as a redshirt freshman guard. The 2-9 Cyclones end their season Saturday at TCU.
"I'm definitely going to miss it, my teammates, my coaches," Gannon said Wednesday night. "I like football again."
Those four words seemed unlikely to ever come out of Gannon's mouth after the way his season began, walking off the field in the middle of a practice, never turning back.
He hadn't felt right since last fall. He was irritable. His thoughts raced. He worried constantly. He struggled to focus at times. His chest tightened and his stomach turned.
Still, he made it through spring practice, summer conditioning and fall camp, just as he had the past four years. He started Iowa State's opener, a loss to North Dakota State, at right tackle. Four days later, during a pass-protection drill in the middle of practice, Gannon hit his breaking point.
"I felt in my mind like I was going to die," Gannon told ESPN.com in his first extensive interview about the incident. "I hadn't had a full-on panic attack [before]. There was no escape. I was trapped.
"I had to get out of there, so I did."
The 6-foot-7, 306-pound Gannon stepped out of the drill, then announced to line coach Brandon Blaney and the group that he was done. Not done with the drill or with practice. Done with football. Forever.
Gannon wasn't sure exactly what had happened. But he knew, or at least thought he knew, the trigger.
"I couldn't even watch football," he said. "It made me think of all the mistakes I made. I hated going to practice because I got anxious. During the games, I would be stressed out full-time.
"I thought I hated the game."
The attack lasted about 20 minutes -- the first 10 were torture -- but the tension subsided as Gannon sat with ISU's strength coach and teammate Tom Farniok in the locker room. It provided affirmation that he had made the right decision. He felt "weightless."
When ISU coach Paul Rhoads found Gannon leaving the team's facility, Gannon told him, "I'm done. I can't do this anymore."
"It was the general feeling about football," Rhoads recalled. "Hated it. Couldn't stand watching it. Didn't want to be around it any more. At the same time, there was, 'I don't want to let my teammates down.'
Gannon waited for the relief to return over the next few days.
"I felt like I was being yanked in half," he said. "I was all tangled up, all these emotions happening. I knew I had to talk to somebody."
Gannon met with Marty Martinez, a psychologist with ISU's student counseling service who had worked with athletes like star wrestler Cael Sanderson. Martinez immediately suspected Gannon had anxiety and possibly an anxiety disorder.
Anxiety ran in Gannon's family, but since he never had discussed his symptoms, his parents, like his coaches and teammates, never suspected it. Hearing about the likely cause of the problem gave Gannon the relief he sought.
"I wasn't going crazy," he said. "Something was really going on."
Football hadn't caused this. No one thing had. Gannon pushed himself in school, majoring in computer science and earning Academic All-Big 12 honors. He soon had to find a job after college and a place to live.
"It's not so much, 'I don't like football anymore,'" Martinez explained. "But because it's happening there, he couldn't escape it. I picked up something deeper, a loyalty that caused him to leave. 'I'm letting my team down. I can't keep doing that.'"
Martinez knew treatment would help Gannon, but he didn't think Gannon would return to the team. Most of the athletes he counsels come before they've quit.
As ISU hosted Kansas State that Saturday, Gannon sat in the house he shares with three teammates. At first he didn't want to watch the game. Waiting for his parents to arrive from Iowa City, he flipped through channels. Nothing was on TV. Eventually, he turned to the game.
"I realized I love football, I miss football," Gannon said. "I wanted to be there with my teammates. That was kind of the turning point. I realized, 'Wow, I want to be back.'"
Blaney received a text-message from Gannon after the game.
"I knew at that point how much he missed being with the guys," Blaney said. "I knew in that text we were going to make headway. Whether or not he was ever going to play another snap for us, it was never important."
Gannon met with Rhoads and Blaney on Sunday and explained what likely had caused his meltdown. He met with Martinez again Monday and then with team physician Marc Shulman on Tuesday morning.
Shulman diagnosed Gannon with generalized anxiety disorder. They set up a treatment plan, which included medication, counseling and biofeedback, a technique that uses electrical sensors to help people better control their breathing.
"It helped him realize football wasn't the problem," said Shulman, who helped basketball star Royce White with his anxiety while at ISU. "You just have anxiety. He said, 'Being able to realize what I was feeling, I've been suffering with this for years. I just never knew how to express it.'"
Gannon continued his treatment and exercising, while talking to the coaches daily. After ISU's win against Iowa nearly two weeks after Gannon first left, Rhoads decided he could return.
He addressed the team at a meeting the next day, tearing up at the end.
"I told the team, 'Jake realizes and I do, not all 125 of you are going to welcome him back. And he's OK with that,'" Rhoads said. "The team responded with instantaneous applause when he got done. It was a true welcome back."
Several teammates told Gannon they had similar symptoms. Rhoads soon referred several players to Martinez for counseling.
"Jacob's opened the door for them," Rhoads said, "that it's not a big deal."
Gannon also re-opened the door to football. He first worked strictly on special teams in his first game back, against Baylor, then regained his starting job the next week at Oklahoma State.
He had a panic attack before the Oklahoma State game, on the bus ride to the stadium. His breathing exercises didn't help.
"What saved him is, 'I'm going to be OK. We know where it's coming from. It's not about football. It's not because I'm not ready,'" Martinez said.
Gannon hasn't had a panic attack for about six weeks. He meets weekly with Martinez and continues his other treatment. He has started the past seven games and has played "at a very high level," Rhoads said.
NFL scouts are noticing and Rhoads thinks Gannon will be in a pro camp, if not a late-round draft pick. He thinks about Sept. 3 almost daily, but he has moved on.
"It's been refreshing just to put away some of that stress and negative feelings, wipe the slate clean," he said. "It was really important to get back to football and enjoy what I'm doing."