Grant Hermanns knew something was seriously wrong with his body.

The rapid weight loss. The dangerously high fevers. The overwhelming fatigue.

They were all ominous signs, but no one could figure out what was ailing the offensive lineman. Hermanns and his family were stumped, and so were his doctors.

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"Really, I was fighting for my life," Hermanns said in an interview with The Associated Press after a recent practice with the New York Jets.

The 23-year-old undrafted rookie out of Purdue is getting a chance to live out his NFL dream, working in training camp at both tackle spots as well as guard for the Jets. Hermanns is driven to succeed, motivated by having overcome a life-threatening staph infection that ravaged his body just a few years ago.

"It’s pretty amazing," Hermanns said. "I always say it’s by God’s grace, man, that I even have my life today and I’m here with this opportunity."

Hermanns was in his senior year at Rio Rancho High School in New Mexico in the summer of 2015. He and his parents were traveling to various football combine workouts, trying to improve his prospects of getting recruited by a Division I team. The Albuquerque native was running the 40-yard dash at a Nike Elite event in Ohio when he suffered a hip avulsion fracture — an injury in which a tendon or ligament pulls off a piece of bone.

Hermanns, who somehow finished the combine, needed several weeks to heal before he started his senior football season and played in six games.

"But then I started getting these weird fevers," he recalled. "I would be at 104 degrees just randomly or I'd go all the way down to 94, a sub-fever. And it would happen all the time, like every other day. I’d be falling asleep in class, just covered in sweat. My parents didn't know what was going on and they took me to the doctor multiple times. The doctor said, ‘You’re fine, nothing’s wrong.’ They tested my white cell count and they couldn’t find anything."

The 6-foot-5 lineman was losing weight at an alarming rate, though, dropping from 265 pounds to 190 in just a few months.

"I looked like a basketball player and I played offensive tackle," said Hermanns, who's now 6-7 and 300 pounds.

His mother Kelli took him to a physical therapist to try to find answers — and the breakthrough came when Hermanns was told to lie on the table. His left hip was raised significantly higher than his right, and the therapist asked him to walk.

"They were like, ‘Oh, that’s not right. You should not be walking like an old man,’" Hermanns recalled.

He went to football practice the next day, used the bathroom and thought he was urinating blood. It turned out — he would later be told — it was liver enzymes leaving his body.

"My liver and some of my internal organs were starting to break down because of the sickness inside of me," Hermanns said.

His mother rushed him to the emergency room, where doctors retraced the previous few months to try to determine what was happening.

They ordered an MRI — and there it was.

"It was a cyst," Hermanns said, "the size of a pomegranate."

Doctors would later tell Hermanns and his family they believe the staph infection might have entered his body through a cut while playing football. It somehow settled into the hip area and began attacking his body over the next several months.

"They still tell me today there’s like a one in a million chance of that happening, and I just got the unlucky bullet." he said. "But I believe everything happens for a reason. And it’s definitely made me who I am today."

With the mystery finally solved, he had surgery the next morning.

"The doctor said when they cut me open, the cyst just exploded out of my hip," Hermanns said. "It was like a geyser right out of my hip."

Surgeons said if Hermanns had been a few years older, the infection might have been fatal; younger patients may be able to better tolerate such a severe case.

Hermanns temporarily lost feeling in his left foot and part of his left leg, and still has numbness in a spot on the leg from nerve damage caused by the cyst. He had to learn how to walk again, and found motivation in an unlikely source.

"My goal each day was to beat the old woman that was walking around the wing," he said with a laugh. "So I had to get on my little walker and practice walking and just get back to it."

Step by step, Hermanns gradually got closer to normal. Football season was over, so he focused on finishing his wrestling season.

"If you know Grant," his mother said in a phone interview, "and you know his power of will — and it’s not willpower with him, it’s power of will — and his ability to focus on something if he really wants it, there’s just no doubt that’s what he’s going to do."

So he trained, regained weight and got back on the mat. Just a few months removed from nearly losing his life, Hermanns was in the New Mexico Class 6A heavyweight state championship.

And won.

"Grant is such an amazing person," Kelli said while choking back tears. "He’s really, truly a gift. ... I am so grateful for him every day. He teaches me all the time how to be a better person."

Purdue gave Hermanns a football scholarship and he redshirted his first season before earning a starting job at left tackle, becoming a mainstay for the Boilermakers for four years. The team co-captain and industrial management major was a member of the Academic All-Big Ten team four times.

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Hermanns is used to overcoming odds and serving as an inspiration. Now he's with the Jets, eager to do it again while making his mark in the NFL.

"I feel I got a second chance at life because I did almost perish at a young age," Hermanns said. "It kind of opened my family’s eyes up, and mine, that all the time we have together is so precious for every one of us. You have to spend it very well and very wisely because it could be gone in an instant."