When she was 12, Chelsea Baker, the only girl in her Plant City, Fla., Little League, made headlines by throwing two perfect games with her signature knuckleball. Two years ago she was offered a contract to play pro ball in Japan. And this year, as a junior at Durant High, she became the first female pitcher on a boys' varsity team in her county, finishing the season with a 3--0 record and a 0.74 ERA in 19 innings. But all that was a warmup for last week, when Chelsea, 17, tossed batting practice for a trio of Tampa Bay Rays stars: Evan Longoria, Jose Molina and David Price. "I'm impressed," said Price, who hit two of her pitches but whiffed on another. Taught to throw the knuckler by one of her first coaches, former MLB pitcher Joe Niekro, Chelsea says her mentor, who died in 2006, would've been proud to see her on a big league stage. "He always told me he taught me the knuckleball because he thought I'd go places."