The fallback plan most athletes talk about became Witherspoon's primary goal.
But during his sophomore year at St. Joe's, Witherspoon got the itch again to compete in a sport. Still, he wanted to find one that would offer the flexibility for him to stay on course for a degree in pharmaceutical marketing.
After talking to his second cousin - two-time world heavyweight champion "Terrible" Tim Witherspoon - he decided to try boxing.
In 2002, Chazz Witherspoon began boxing at Joe Hand's Police Athletic League Gym.
A year after taking up boxing, Witherspoon won a Pennsylvania State Golden Gloves title. In 2004, he placed second in the U.S. Boxing Championships and was an alternate for the 2004 Olympics in Athens, Greece.
His rapid progress in amateur boxing surprised even him.
"When I came into boxing," Witherspoon said, "I had a goal and my goal was to just make the Olympic trials. I ended up surpassing my goal by becoming an alternate."
On Dec. 12, 2004, Witherspoon knocked out James Daniels in his first professional fight. The die for his career had been cast.
But despite deciding to become a professional boxer, Witherspoon stayed true to his academic pursuits. He graduated from St. Joe's in 2005.
"I believe I would have been a pharmaceutical [representative]," Witherspoon said of what he'd be doing had he not taken up boxing. "I would have been the guy that you see in the doctor's office with the briefcase.
"I would definitely use my degree and utilize my degree. I'd be a salesman, basically."
For now, that's still down the road.
On Saturday in Atlantic City, Witherspoon (30-2, 22 KO) has the opportunity of his boxing career as he fights undefeated prospect Seth Mitchell (24-0-1, 18 KOs) for the vacant North American Boxing Organization heavyweight title.
It's a big fight for the 30-year-old. A win on the HBO-televised event could lead toward that elusive world title fight and the riches that go with it.
"Yeah, I know it's an important fight," said Witherspoon, who is in the co-main event with the rematch between Philadelphia's Bernard Hopkins and Chad Dawson for the World Boxing Council's and The Ring magazine's light-heavyweight championship. "As far as the last time to shine, I don't look at it like that.
"But it's definitely an important fight, and I don't take it lightly. It's imperative that I win this fight in order to put my name in the mix of being a contender or being in the top 10."
Boxing is a sport of limited opportunities. A loss at the wrong time can quickly knock you from rising contender back to club fighter.
Witherspoon knows firsthand, because in 2008, after a 23-0 start, he lost by disqualification to fellow undefeated prospect Chris Arreola. Arreola went on to get a heavyweight title shot against WBC champion Vitali Klitschko.
Witherspoon's other loss was to Tony Thompson, who is scheduled for a rematch with World Boxing Organization and International Boxing Federation champion Wladimir Klitschko on July 7 in Switzerland.
Witherspoon, meanwhile, is trying to rebuild his status.
"Well, I know a win against Seth would revitalize my career," Witherspoon said. "I always speak to the fact that boxing is a sport that, as soon as you lose one or two fights, it's like your career is over.
"I don't really understand that, but I know it'll revive my career, because in boxing, you're only as good as your last win. [A victory over Mitchell] would put my name back in the mix."
Mitchell, like Witherspoon, is a college graduate. He played linebacker at Michigan State. He didn't turn professional until 2008, when he was 26. But Mitchell has risen quickly and was named one of ESPN.com's Prospects to watch in 2011.
Mitchell has won nine consecutive fights by knockout.
"Unlike Chazz - he had an academic scholarship - I consider myself a C student. But I work extremely hard," said Mitchell, who has a degree in criminal justice.
"As easy as athletics came to me, it was as hard in the classroom. But I had the wherewithal to work hard and stay determined. There was no doubt I was going to graduate when I went to college."
Because of their late starts, both Witherspoon and Mitchell are trying to defy the conventional wisdom that says top fighters must make a full-time commitment to the sport by the time they are 13 or 14.
But of his academic experience at St. Joe's, Witherspoon said: "I think being in school and doing the studying and being in academia like that, I've learned that I can do whatever I put my mind to.
"I think that's the big thing that comes out of that for me.
"Everything is starting to come together. I just plan on going out there and putting on my best performance."
Contact John Smallwood at email@example.com. For recent columns, visit www.phillynews.com/Smallwood.