Maryland's major prep race for the Triple Crown takes place Saturday at Pimlico as a field of six 3-year-olds meet in the $125,000 Federico Tesio Stakes. The Tesio is the headliner on a card that features four other stakes races.Three horses nominated to the Triple Crown are in the line-up. They are Nancy Albert's Magic Weisner, Susan Evans' The Sewickley Kid, and G. Three Stable's Smoked Em. Tony Dutrow's entry of Derby Drive and Radio One, along with Joseph Graffeo's Heir D'Twine, complete the field.Of the three Triple Crown nominees, only Magic Weisner has won a stakes race. The son of Ameri Valay is riding a five-race win streak that includes four added-money victories at Laurel Park since New Year's Eve. He won the Maryland Juvenile Championship for Maryland-breds by a half-length in December; the Goss Stryker Stakes, also for Maryland-breds on Feb. 9; the restricted Deputed Testamony Stakes on March 2; and the open-company Private Terms Stakes on March 30. Jockey Phil Teator rides for owner-trainer-breeder Alberts.Alberts has dropped Magic Weisner from consideration for the Kentucky Derby (gr. I), but said in a conference call earlier in the week that her colt could start in the May 18 Preakness Stakes (gr. I) should Magic Weisner advance through the Tesio.The Sewickley Kid (to be ridden byMark Johnston) and Radio One (Mario Pino) tested and finished behind Magic Weisner during his win streak. The Sewickley Kid was second in the 1 1/8-mile Private Terms, while Radio One finished third in the seven-furlong Stryker.Two New York shippers have designs on knocking off the favorite. Heir D'Twine (Ramon Dominguez) tried grade III company in the Gotham Stakes last out and finished fourth. Smoked Em (Richard Migliore) made his stakes debut in February's Whirlaway and was moved up to 2nd via disqualification. He since finished third behind Heir D'Twine in a March 3 allowance race at Aqueduct.The local hitter with the best chance to upend the favorite is Derby Drive, who shipped to Turfway Park in late March and finished third after stumbling at the start.The four stakes which make up the under-card on Spring Challenge Day are all Maryland-bred events. They are the $100,000 Jennings Handicap, where last year's Pimlico Special (gr. I) winner Include is back to defend his crown; the $100,000 Geisha Handicap; the $75,000 Caesar's Wish; and the $60,000 Star De Naskra.The Tesio will be featured on ESPN 2 on a tape delayed basis (Saturday-6-7 p.m. EDT) along with Saturday's other Triple Crown prep, the Coolmore Lexington Stakes (gr. II) from Keeneland.