All he has to do is beat Michael Phelps - and become the villain of the Beijing Games.
Crocker, a soft-spoken native of Maine who loves strumming his guitar, writing thoughtful blogs and cruising around in vintage cars, appears to be the last major hurdle to Phelps' bid to surpass Mark Spitz with eight gold medals.
They'll face each other Saturday morning in the final of the 100-meter butterfly, Phelps' last individual event of the Olympics and Crocker's only one.
What must be going through this guy's mind? He's not about to apologize for wanting to win the first individual gold medal of his career. Then again, he surely knows that a whole world is cheering on Phelps, eager to see him do something no Olympian has done before.
"You can start by not worrying about what everybody else thinks," Crocker said. "Nobody knows what I've really gone through in the last eight years and what has gotten me to this point, besides myself and a few people that I know well. So it's my own personal deal at this point."
Crocker is certainly a formidable foe, holding the world record in the 100 fly for more than three years. But Phelps won their most important showdown at the 2004 Athens Olympics. He also came out on top at last year's world championships and last month's U.S. Olympic trials.
After waiting around all week to race at the Water Cube, Crocker inexplicably wore a jammer - a suit that runs from the waist to just above the knees - and came shockingly close to getting bounced in the preliminaries.
Switching back to his regular legsuit for Friday's semifinals, Crocker was much faster. He tied for the third-best time, trailing the top qualifier, Serbia's Milorad Cavic, and Phelps.
Crocker returned in the evening to swim the butterfly leg in the prelims of the 400 medley relay, which could be the crowning race of Phelps' monumental achievement.
"I feel like I'm at a swim meet now," Crocker said. "I get sharper and sharper with each race I do, a little bit more confident about exactly what I'm doing at certain points in the race, how to build the race properly."
Everyone on the U.S. team played it safe, no doubt remembering what happened to Crocker at last year's worlds. Phelps had already won seven events and was resting up to swim in the final of the medley relay. He never got the chance — Crocker jumped in too quick on an exchange and the U.S. team was disqualified in the prelims.
"I don't think we were going to leave China if anyone got us DQed," quipped Matt Grevers, who swam the backstroke leg. "It's such a historic event on the line with this relay. This relay might be what it all comes down to for the eight golds. You don't want to be the one who screws that up."
The blunder was certainly on Crocker's mind when he climbed on the block to swim the butterfly leg.
"That's kind of hard to forget," he said. "After this week, with all Phelps has done, you don't want to be the guy standing in the way of that."
But that's exactly what Crocker will be in the 100 fly.
The guy standing between Phelps and destiny.
The potential bad guy.
"People point at me, but Cavic is looking real good and a lot of other guys are looking really good," Crocker said, trying to deflect as much attention as possible. "It's going to be a tight race all across the board."
Phelps agreed. He hopes to get off to a better start so he doesn't have too much ground to make up on the return lap. If he's close, it's over - no one is a better closer.
"For me to be a player in that race, I have to be closer at the 50," he said. "If I'm not, then it will be tough. I was over a body length behind at the 50 in the prelims and came up a bit short, so I have to be there."
Friday was another big day for the Americans at the pool. In addition to Phelps, Ryan Lochte won his first individual gold medal by beating teammate Aaron Peirsol with a world record in the 200 backstroke, while Rebecca Soni claimed a record of her own to beat Australia's Leisel Jones in the 200 breaststroke. Also, 41-year-old Dara Torres advanced to the semifinals of the 50 freestyle - her only individual event in Beijing.
With two days of swimming left, the powerful U.S. team has piled up 25 medals, including 10 golds. The Americans are on course to eclipse the 12 golds and 28 medals they won in Athens four years ago and possibly challenge their 14-gold, 33-medal haul at the 2000 Sydney Games.
Of course, it helps to have a swimmer like Phelps, virtually a country unto himself.
"I never thought I would see this type of swimming in my life," Grevers said. "This is absolutely going to be something for the ages. A hundred years from now, people will probably remember this Olympics and what Team USA did, and especially what Michael did."
Phelps has become a household name around the world, touted in headlines as everything from the "Barracuda from Baltimore" to the "God of Olympia." Even in China, where the home team's success is getting most of the attention, the official news agency dubbed Phelps the "American superfish."
For those who believe Phelps might be using more illicit methods to produce these times, he shot down any speculation about doping.
"Anybody can say whatever they want, but I know I'm clean," said Phelps, who took part in a special U.S. anti-doping program that subjected him to additional, more sophisticated testing. "People can question it all they want, but the facts are the facts. I have the results to prove it."
On Friday, he won No. 6 with another world record - the sixth one of those, as well - in the 200 individual medley. He returned a half-hour later for the butterfly semifinals, so rushed after the medal ceremony that he had to stuff the latest gold in the pocket of his warmup jacket.
"There wasn't much time," Phelps said, "but I think there's going to be a lot of time for me to rest over the next 18 hours or so, and I'll be able to be ready."
The 23-year-old hung on the lane rope in a familiar pose after winning the 200 IM, but showed little emotion other than raising his left arm when his time of 1 minute, 54.23 seconds flashed on the board - more than two seconds ahead of the next guy.
"The next two races are pretty important," said Phelps, who erased his own mark of 1:54.80 at last month's U.S. trials. "I have to conserve as much physical and emotional energy as I can."
He's already the winningest athlete in Olympic history with 12 golds - he also won two bronze medals in Athens - but his sights are on eight in Beijing.
Spitz won seven golds at the 1972 Munich Games. Phelps has two more events to remove any doubt he's the greatest Olympian ever.
Lochte tried to pull off a daunting double, going against Phelps just 29 minutes after winning the 200 backstroke. He couldn't keep up, though he did hold on for bronze. Laszlo Cseh of Hungary picked up his third silver of the games - all of them trailing Phelps.
"It's not a shame," Cseh said, "to be beaten by a better one."
When the official times were posted, Phelps extended his right hand to Lochte in the next lane. The friends shook hands and patted each other on the head. Later, they yukked it up on the medal stand before Phelps hustled off to grab his racing gear.
"I switched from my dress sweats to my parka, shoes, threw my cap and goggles on and then they pushed us on out. No time," he said.
History can't wait.