BERKELEY -- Standing on the UC Berkeley baseball diamond he called home before the major leagues beckoned, Tyler Walker bent down to retrieve an errant ball.

"I haven't picked up one of these in a while," said Walker, a former San Francisco Giants player who figures a shoulder injury has ended his baseball career but freed him to pick up the education he quit for the game.

Much of the Berkeley campus is far less familiar than the baseball to the former pitcher, who recently enrolled in undergraduate classes for the first time in 13 years.

Like dozens of other elite Cal athletes who left school early for big-league sports careers, Walker is using the university's degree-completion program for former Cal players. College athletes with big-money futures increasingly feel the need to improve their academic performance, and UC Berkeley is one of the few schools nationwide trying to bring them back. NBA star Jason Kidd and NFL MVP quarterback Aaron Rodgers are on its wish list.

The program, run out of the campus Athletic Study Center, is open to any former student interested in finishing his or her schoolwork. But its main focus is on athletes like Walker, who after three years of college was drafted in the second round by the New York Mets in 1997.

Trying to figure out which classes to take after several years out of higher education may not be as intimidating as facing down slugger Albert Pujols, but Cal helps athletes handle the bureaucratic and financial fastballs. The university has "a lifelong commitment" to the athletes it recruits, said Derek Van Rheenen, who directs the Athletic Study Center. "It's the right thing for a university to do."

About 100 former athletes have returned to UC Berkeley in the completion program's six or so years, Van Rheenen said. About a dozen are enrolled this year, including Walker and former basketball star Shareef Abdur-Rahim.

"I really can't do anything moving forward without a college degree," said Walker, 35, who plans to major in political science. "Having a baseball career helps a résumé, but I can't even coach college baseball without a degree."

Only a handful of other universities with big-money sports programs, including the Ohio State University and the University of Kentucky, have similar programs for athletes. Stanford University, however, does not, said spokesman Jim Young -- mainly because nearly all athletes graduate before leaving school.

Low graduation rates among college athletes are embarrassing, said John Thelin, a University of Kentucky professor who has written about the uncomfortable intersection of higher education and sports. Some schools, for example, bring in scores of athletes for one year before they leave to become professionals in their sports.

Degree-completion programs are a result of the embarrassment over that "one-and-done" strategy, he said. "It's probably some latent sense of responsibility, perhaps even guilt," Thelin said. "There's long been this sheepishness (about college athletics)."

Although returning elite baseball, football and basketball players rarely have trouble paying tuition and other costs, other athletes sometimes find finances difficult, Van Rheenen said. Athletic departments are not allowed to support athletes who have used up their college eligibility, so Van Rheenen and his staff try to find other scholarships for returning students who may not come back as millionaires.

There is little direct benefit for the university when athletes finish their degrees, Van Rheenen said. Re-recruiting the athletes essentially acknowledges that the school values them for their academic achievements as well as their athletic accolades, he said.

"My philosophy, shared by many educators, is that then the institution must make a long-term commitment. It may even be 30 years down the road when they want to complete their degree."

The NCAA should change its rules to make it easier for athletes to finish degrees, he said.

"In some ways, these athletes have helped the bottom line of the athletic department," he said. "It seems reasonable for the athletic department to support them."

NCAA officials said they were not sure how many schools had degree-completion programs, but they noted that 88 percent of Division I athletes receive bachelor's degrees by the time they turn 30.

Fame and fortune is not all that lures young athletes away from their degrees.

Swimmer Anthony Ervin, who won gold and silver medals at the 2000 Olympics while a UC Berkeley student, gave up both swimming and school in 2003 to play rock music in New York. He got tattooed and began smoking.

"I just knew that I wasn't ready" to finish school, he said on the Berkeley campus, to which he returned in 2008. "There was no thirst that I needed to quench in the academic sphere. I just needed to go live life for a while."

After returning to Cal, Ervin quit smoking, started swimming again and, with Van Rheenen's help, finished his bachelor's degree in English. The 30-year-old Southern California native is working on a master's degree and is among the favorites to make the U.S. team for this year's Olympics in London.

"Maybe you should be a few years older to truly appreciate what a university has to offer," Ervin said.

Being older has certainly changed Walker's experience, although he still parks at his old fraternity house near the campus.

"You look around the room and you hear kids talking about fake IDs and parties," said Walker, whom students occasionally recognize. "I feel like a total dinosaur."

Matt Krupnick covers higher education. Contact him at 510-208-6488. Follow him at Twitter.com/mattkrupnick.