Racing fans who already have Derby fever might experience a spike in temperature at about 5 p.m. Saturday.

That’s when last year’s juvenile champion Shanghai Bobby and nine other 3-year-olds will be heading toward the starting gate for the $400,000 Holy Bull Stakes (Grade 3) at Gulfstream Park.

The Holy Bull is 1 1/16 miles, with a run of only about 80 yards to the start of the first turn.

Saturday’s co-feature is the Forward Gal (Grade 2) at seven furlongs on dirt for 3-year-old fillies.

The Holy Bull is always an important early prep race for the Florida Derby at Gulfstream on March 30 and the Kentucky Derby at Churchill Downs in Louisville, Ky., on May 4.

The Holy Bull will be the first 2013 start for Shanghai Bobby, who won all five of his starts last year, including four stakes races.

The second choice in the betting could be Itsmyluckyday, who on Jan. 1 won the one-mile Gulfstream Park Derby in the fast time of 1:34.39.

Shanghai Bobby, trained by Todd Pletcher, has not raced since Nov. 3 when he won the 1 1/16-mile Breeders’ Cup Juvenile (Grade 1) at Santa Anita Park in Arcadia, Calif.

Rosie Napravnik, who rode Shanghai Bobby in all of his 2012 races, will be in from Fair Grounds in New Orleans for the Holy Bull.

Paco Lopez, who rode Itsmyluckyday in the Gulfstream Park Derby, will ride Bern identity in the Holy Bull.

Last fall, Lopez rode Bern Identity in a win and a second-place finish in stakes races at tracks in Louisiana.

“Paco had a previous commitment with Bern Identity,” said Eddie Plesa Jr., the trainer of Itsmyluckyday.

Plesa has a capable replacement in Elvis Trujillo, who will ride Itsmyluckyday for the first time in a race.

Trujillo rode Itsmyluckyday on several recent mornings at Calder, including a fast-timed workout.

The Holy Bull also has Frac Daddy and Dewey Square, the second- and third-place finishers last Nov. 24 in the 1 1/16-mile Kentucky Jockey Club Stakes at Churchill Downs.

Post positions could prove important, with horses on the outside facing the prospect of being forced wide on the first turn.

Shanghai Bobby has the rail, and a good break from the gate could set him for a clean run with his early speed.

Bern Identity, in post four, and Itsmyluckyday, in post seven, have stalking styles.

The $400,000 Fountain of Youth (Grade 2), at Gulfstream on Feb. 23, also is 1 1/16 miles. The $1 million Florida Derby (Grade 1) is 11/8 miles.

Forward Gal

Kauai Katie, trained by Pletcher, is the likely heavy favorite in the six-horse Forward Gal field. On Jan. 1 at Gulfstream, she won the six-furlong Old Hat Stakes (Grade 3) in a fast time of 1:09.66.