There will be no shortage of challengers when Kentucky Derby winner Mine That Bird tries to win the Preakness Stakes on Saturday. The Preakness is limited to 14 starters, one of which will be filly Rachael Alexandra, who was the smashing 20 length winner of the Kentucky Oaks.

In winning the Oaks by a record margin, she ran a 108 Beyer speed figure compared to Mine That Bird's Derby win which was accomplished with a 105 Beyer and marked the first time since the speed figures have been used that the Oaks winner ran faster than the Derby winner. Rachael Alexandra will attempt become only the fifth filly to win the Preakness in 133 tries.

The field for the second leg of the Triple Crown grew to ten with Musket Man, General Quarters and Terrain the latest confirmed starters for next Saturday’s race. Musket Man was third in the Derby and General Quarters was 10th. Terrain was fourth behind winner General Quarters in the Blue Grass on April 11 in his last start.

Musket Man won five of six starts before finishing about seven lengths behind 50-1 long shot Mine That Bird in the Derby. The colt has finished in the money in all seven career races for owner Eric Fein. Plans call for a Tuesday workout at Monmouth before Musket Man is vanned to Pimlico as late as possible, likely next Friday. Eibar Coa has the mount.

Terrain was declared in after a 1 1/2 -mile gallop at Churchill. Trainer Al Stall Jr. planned to run Terrain in Saturday’s Lone Star Derby but changed his mind after the Derby.

General Quarters came out of the Derby in top shape, and galloped Wednesday morning at Churchill Downs. Tom McCarthy’s colt will be vanned to Pimlico on Tuesday. Jockey Julien Leparoux has the call.

They will be joined, Papa Clem, Flying Private, Big Drama, unbeaten Hull and Take the Points. Papa Clem was fourth in the Derby and Flying Private was last of 19. Derby runner-up Pioneerof the Nile remains a possible starter.

Big Drama, who finished first in the Swale Stakes but was disqualified and placed second, arrived at Pimlico on Wednesday after a 19-hour van ride from Calder Race Course in Miami. John Velazquez will be the rider. Flying Private is trained by D. Wayne Lukas, the Hall of Famer who has won 13 Triple Crown races, including the Preakness five times.

Other 3-year-olds under consideration are Friesan Fire, Conservative, Sky Gate and Tone It Down, who finished third in last Saturday’s Tesio Stakes at Pimlico. Mine That Bird, meanwhile, galloped twice around Churchill Downs through a light drizzle Wednesday with exercise rider Charlie Figueroa up.

As the Preakness draws closer all online horse betting eyes will be on Rachael Alexandra, who appears to have run out of female competition and who many pundits firmly believe could have won the Kentucky Derby. If you bet on horse, you probably agree she has a good shot at beating the boys.

The record victory of margin in the "The Run for the Black-Eyed Susans" is 11½ lengths, by Smarty Jones in 2004. It's a strong field including several runners that can threaten that record. Add in there's a Triple Crown hopeful and a lady taking to post in Saturday's event, and you have all the makings for a historic 134th Preakness Stakes. BetPhoenix Racebook is happy to be your hosts.