FAIR HILL, Md. - It isn't that Animal Kingdom can't handle crowds and chaos. By winning the 137th Kentucky Derby amid all its sound and fury, the colt surely demonstrated certain degrees of resilience and adaptability.

Nehro, the Kentucky Derby runner-up, will not run in the Preakness Stakes on Saturday at Pimlico, owner Ahmed Zayat said early Tuesday morning.

"It's a very hard decision, but I want to err on the side of caution," Zayat said. "He couldn't look any better. His work on Monday was absolutely awesome. I'm just concerned about him having four hard races in eight weeks, even if, outwardly, he doesn't appear to be showing it.

ELMONT, N.Y. - Mucho Macho Man, who finished third behind Animal Kingdom in the Kentucky Derby, worked a half-mile in 49.21 seconds Tuesday morning over a sealed, sloppy Belmont Park training track, his final major piece of training before Saturday’s $1 million Preakness Stakes at Pimlico.

Jockey Rajiv Maragh was up for the move, which Daily Racing Form timed in fractions of 12.27 seconds for the opening eighth, 24.09 for the quarter and 49.21 for four furlongs. He galloped out five furlongs in 1:03.70.

Led by Animal Kingdom, the winner of the Kentucky Derby, an intriguing mix of Derby participants and Triple Crown newcomers is set to be entered Wednesday in Saturday’s 136th Preakness Stakes at Pimlico Race Course in Baltimore, but the final composition of the field was still in flux Monday, owing to the difficulty owner Ahmed Zayat was having deciding on whether to run Nehro, the Derby runner-up.

Fans of Animal Kingdom will have to look elsewhere for any kind of betting value on the 2011 Preakness Stakes. The Kentucky Derby champ surely will have short odds -- DRF's Mike Watchmaker has him as a 5-2 favorite on his early Preakness line.

Midnight Interlude, who finished 16th in the Kentucky Derby after capturing the Santa Anita Derby, tuned up for Saturday’s Preakness Stakes at Pimlico with a three-furlong drill in 35.60 seconds on Monday morning at Churchill Downs.

“He went very nice, with a lot of energy,” said his trainer, Bob Baffert, who was at Churchill Downs for the work. “It was probably his best work over the track since we got here.”

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Wyomia, the runner-up in the Grade 1 Ashland Stakes at Keeneland last month, is among the seven 3-year-old fillies entered to run Friday in the Grade 2, $250,000 Black-Eyed Susan Stakes, the anchor of the Preakness eve card at Pimlico Race Course in Baltimore.

Julien Leparoux is named to ride Wyomia in the 1 1/8-mile Black-Eyed Susan, which is to the Preakness what the Kentucky Oaks is to the Kentucky Derby. Trained by Curtis Garrison, Wyomia was beaten a length by Lilacs and Lace in the April 9 Ashland. The daughter of Vindication was assigned post 4.

LOUISVILLE, Ky. – With owner Ahmed Zayat watching from the grandstand, Kentucky Derby runner-up Nehro breezed a half-mile in 50.80 seconds over a sloppy Churchill Downs racetrack early Monday morning, leaving Zayat trying to decide whether to send the colt to the $1 million Preakness.

King Congie, beaten only a head when third in the Grade 1 Blue Grass Stakes last month, worked five furlongs in 1:04.60 Sunday morning over a good Belmont Park main track in preparation for a start in Saturday’s $1 million Preakness Stakes at Pimlico.

 Though the time may not seem like much, consider that the work was done around a set of traffic cones, referred to as dogs, forcing the move to be conducted toward the middle of the racetrack. Horses usually work along the rail. Belmont clockers timed King Congie’s final quarter in 24 seconds.

Dance City, who is expected to be a major pace factor in Saturday's Preakness Stakes, and Saratoga Red, whose participation in the second leg of the Triple Crown hinges on the size of the field, both worked five furlongs on an off track on Sunday morning at Churchill Downs.