Over 10-plus years of development, John Travolta, Denzel Washington, and Michael Keaton were all supposed to star as the bigheaded baseball king who comes out of retirement to earn back three newly disqualified hits that guarantee his spot in the Hall of Fame. Finally, the role fell to Bernie Mac, a sitcom star and movie sidekick (''Charlie's Angels 2'') who's looking to ace the transition to leading man. ''It fit me,'' says Mac. ''As an actor, as a comic, and as my first lead.'' Director Charles Stone (''Drumline,'' ''Paid in Full'') says he butted heads with the studio because he wanted to play down ''3000'''s ''tomfoolery'' to make room for the heart. ''The comedy is secondary,'' Stone insists. ''For this film to go down with ''Field of Dreams,'' ''The Natural,'' and ''Bull Durham,'' it had to have a level of integrity that takes it out of the bounds of slapstick, to where people take this character seriously despite the humor.'' Mac welcomed the dramatic challenge. Working with Angela Bassett, who plays an ESPN correspondent, also improved his game. ''She threw it at me, and I caught it,'' Mac promises. ''He did,'' coos an admiring Bassett. ''He did.''
What's at stake He caught it, but can he hit it out of the park?