(MONEY Magazine) – What do more than 43 million workers have in common with a legendary 79-year-old baseball player? As was the case with Sam "Jet" Jethroe (pictured at right), who broke the Boston Braves' color barrier and became the 1950 National League Rookie of the Year, they are working for employers who don't offer them a pension. But Jethroe stood up to major league baseball and is now eligible to start getting the $10,000 annual pension he deserves. His story also resonates among folks who expect to qualify for a pension. Reason: New data from the Pension Benefit Guaranty Corporation shows that more than 8% of retirees who got lump-sum payouts from small pension plans in 1994-95 were underpaid, often by $1,000 or more.

Jethroe's tale is a mixture of workplace discrimination and pension legalese. Until 1980, professional baseball players had to play four years in the majors to get a pension (today, an appearance in just one major league game qualifies). So although Jethroe had spent six years with the Negro League's Cleveland Buckeyes--not a major league team--and more than three years combined with the Boston Braves and Pittsburgh Pirates before being transferred to the minors in 1954, he didn't qualify for pension benefits. He sued, charging discrimination, among other things. Major league baseball's governing executive council finally offered to give 80 or so players, including Jethroe, an annual pension of $10,000. "I could sure use it," says Jethroe, who lives in Erie, Pa. on next to nothing.

Here's what you can do to avoid striking out in retirement:

--Learn what you're due. If you're covered by one or more employer-sponsored retirement plans, request a copy of the summary plan description and your individual benefits statement; you can get them from your human-resources department or your plan administrator. Be sure to secure one for all the plans where you've earned benefits. Make certain that your benefit calculation matches the formulas outlined in the plan summary.

If it looks like the benefits you are due to receive--or are already getting--are less than you are owed, get in touch with your plan's administrator to try resolving any discrepancies. If the company stonewalls, consider hiring a pension lawyer. Another option: The private National Center for Retirement Benefits in Northbrook, Ill. will check your benefit calculation and even haggle with your former company on your behalf if the researchers believe you've been underpaid. The service is free if it turns out your pension is accurate. But if the pension police find an error in your favor, they'll keep as much as 30% of the difference.

--Push for a pension plan if your current employer does not offer one. "Encourage your boss to start a plan," suggests Trip Reid, a lawyer for the Pension Rights Center in Washington, D.C. Legislation enacted last summer made it easier and cheaper for small companies to provide retirement benefits through so-called Simple 401(k) and IRA plans. For a Simple brochure, call the Labor Department's hotline at 800-998-7542.

--Kelly D. Smith