Exercise rider Dominic terry takes Preakness favorite Rachel Alexandra around the track Friday at Pimlico Race Course in Baltimore.

Baltimore ? Calvin Borel has complete confidence his horse will win the Preakness, the kind of gravitas expected from the Kentucky Derby-winning jockey.

Except Borel won’t be riding the Derby winner today.

He made the unprecedented decision to get off Mine That Bird and onto Rachel Alexandra, the spectacular filly who is the 8-5 early favorite for the second leg of the Triple Crown.

“It’s hard to leave a Kentucky Derby winner,” jockey Robby Albarado said. “You’re the only one with the chance of winning the Triple Crown. It’s a hard decision to make.”

Mine That Bird is the co-third choice at 6-1 with Friesan Fire, the Derby wagering favorite who staggered home next-to-last on the first Saturday in May.

“The 12 other horses are going to have to run the race of their life or me fall off or something stupid happen,” Borel said by phone Friday from Louisville, Ky., where he took a break from mowing his lawn to chat.

“I just got to point her in the right direction, and she’ll get me there.”

If that happens, Rachel Alexandra would become only the fifth filly to win the Preakness. Ten have tried since Nellie Morse in 1924 was the last to wear the winner’s blanket of black-eyed Susans.

If Mine That Bird should win and set up a Triple Crown try in the Belmont next month, well, Borel can take some of that credit, too.

He has permission to help the enemy — virtually verboten in a major race — by talking to Mine That Bird’s new rider Mike Smith. At trainer Chip Woolley Jr.’s request, Borel agreed to go over a few things with Smith this morning.

“He ain’t no dummy,” Borel said. “I’ll tell him what I think, and it’s up to Mike. He knows his horses. It’s kind of hard for me to tell him how to ride a horse.”

Borel said he’s helping as a thank you to Woolley and his camp for putting him on his second Derby winner in three years.

Smith comes in with his brown eyes wide open. The Hall of Fame jockey has ridden in the Preakness 10 other times, winning it with Prairie Bayou in 1993.

“Calvin will just tell me to go to the lead,” Smith said, joking.

Smith also sought advice from his girlfriend Chantal Sutherland. She rode Mine That Bird to three consecutive wins in Canada, where the colt was a champion 2-year-old. Sutherland will be watching Saturday from Woodbine, where she rides.

Smith plans a strategy similar to the one Borel used in the Derby, taking Mine That Bird off the pace and waiting patiently before making a big closing run.

“Hopefully get him in rhythm and he punches like that again,” Smith said.

Some things are different this time, though. Pimlico’s dirt track is known to favor horses running at or near the lead, which is Rachel Alexandra’s favorite place to be. She’ll start from the No. 13 post on the far outside; Mine That Bird is in the No. 2 post.

The surface isn’t as deep as Churchill Downs, which was mired in mud and bogged down most of the 20 horses on Derby Day. The forecast today is for a 30 percent chance of isolated thunderstorms and a high of 80.