Hall of Famer Reggie Jackson thinks all of Alex Rodriguez's numbers are tainted because of his admission to performance-enhancing drug use. Jackson also doesn't believe players who used steroids should be allowed into the Hall of Fame.

"Al's a very good friend," Jackson said of the New York Yankees third baseman in the latest issue of Sports Illustrated. "But I think there are real questions about his numbers. As much as I like him, what he admitted about his usage does cloud some of his records."

Jackson is a special adviser to the Yankees and frequently is around the clubhouse.

In February 2009, Rodriguez only admitted to using steroids during a three-year stretch after he signed a $252 million contract with the Texas Rangers.

Entering this weekend's series with the Boston Red Sox, Rodriguez has 642 career home runs, placing him fifth all-time. After this season, A-Rod, who turns 37 this month, has five years left on his contract. He is hitting .266 with 13 homers and 36 RBIs this year.

After being traded to the Yankees and then opting out of his contract, Rodriguez was re-signed by the club in 2007 to a 10-year deal that includes multimillion-dollar incentives for tying home run milestones such as Willie Mays' 660 figure and Barry Bonds' all-time record of 762. The bonuses, which could total $30 million, were agreed upon before Rodriguez' admission to PED use.

If someone such as Rodriguez or Bonds or anyone else that has been linked to PED use is voted into the Hall by the Baseball Writers' Association of America, Jackson predicts there will be a boycott.

"If any of those guys get in, no Hall of Famer will attend," Jackson told SI.