(CNN) When Lawson Craddock set off on his first Tour de France in July, he knew the course would be challenging.
But he had no idea the next three weeks would involve so much pain.
Craddock ran over an errant water bottle and crashed on the very first day, fracturing a shoulder blade and gashing his face above his left eye.
He had 80 kilometers to ride before he could get a diagnosis, then deliberated on whether to carry on for the next 3,400 kilometers.
"It was definitely not the Tour de France that I imagined," the 26-year-old Houston native told CNN Sport. "I pretty much knew immediately that there was damage to my shoulder. I had blood pouring down my face, and it's pretty disappointing to start the Tour de France that way."
Remarkably, the prospect of riding with intense pain for 20 days -- and perhaps suffering more damage -- didn't dissuade him.
And despite the dubious honor of coming last of all the 145 finishers in Paris -- known as the "lanterne rouge" -- Craddock was far from a loser.
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His determination was fueled in the first place by missing most of 2017 with overtraining syndrome.
"I missed the Tour de France last year and it was a big disappointment, so I knew the feeling of being at home watching it on the couch knowing that you should be there," he said.
"I didn't want that feeling in July again, so I put in a ton of work just to make the team this year and return to the highest level in cycling.
"Halfway through the first stage with the prospect of going home (was), to me, more painful than pushing through the discomfort in my shoulder and fighting on until the finish."
Then there was his pledge to help rebuild his hometown velodrome in Houston, which had been damaged by Hurricane Harvey last year.
Through his shoe sponsor, Craddock had already organized an auction for a pair of custom cycling shoes. But he raised the ante with a crowdfunding campaign launched with his $100 pledge for each stage he could finish with his injuries.
"After the crash I wasn't sure I would be there long enough to see the auction continue, so I was just kind of looking for other ways to help out," he explained. "That's where the inspiration came from."
As the support poured in for Craddock's cause -- it has now gone beyond $250,000 -- his confidence and determination to finish cycling's holy grail continued.
"It blew my mind how quickly it really took off," he said. "The first thing I looked at in the morning and the last thing I looked at before going to bed was the progress we'd make for the velodrome.
"To see the way it grew and people's generosity is really what kept me in the race, and what kept me inspired."
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Craddock endured some hairy moments, particularly navigating the 13-mile cobblestone stretch of Stage 9 near the Belgian border, which he described as "suffering like I've never experienced before."
"The Tour de France is so brutal in the first place, it's difficult enough just to make it through healthy," he said. "I couldn't sit the way that I normally sit, I couldn't ride the way that I normally rode, so it was incredibly challenging.
"A lot of different things kept popping up in my head. I woke up every morning not sure if I was going to be racing the next day or if I was going to be on a flight home that night."
Racing for the Colorado-based EF Education First team, Craddock was dosed up on over-the-counter painkillers, though he still experienced "a lot of discomfort in the shoulder, for sure."
"A lot of muscles just surround the area and kind of seize and contract around the fracture, trying to just protect it," Craddock explained, adding that he underwent "daily rehab and massages just to handle the load."
"While it wasn't ideal, we were able to work with what we had," he said. "Fortunately, I had great staff working on me all the time."
Craddock was also aided by a wrist monitor that kept track of his sleep, along with his general fitness, and allowed him to "just put a number on how my recovery has gone."
"So all these small things we were able to piece together, and things like that kept my body able to compete," he said. "It was just three weeks of just pushing my body past limits that I didn't really know existed."
On July 29, Craddock rode the final stretch of the Tour de France, down Paris' Champs-Élysées and past the Arc de Triomphe, with his wife, parents and brother cheering him on.
His overall time put him more than four-and-a-half hours behind winner Geraint Thomas, but he was probably the happiest last place finisher in history.
"It was a big weight off my shoulders, literally," he said.
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"As a professional athlete, you love to push your body to the limit and beyond," he said. "I want to go back in the future and get another crack -- hopefully healthy next time."