Amongst the most coveted prizes for three-year-old fillies in North America is the Grade 1 Kentucky Oaks, run over 9 furlongs at Churchill Downs the day before the Kentucky Derby. As many as 13 fillies have accepted for the Longines-sponsored $1,000,000 event at 5:49 p.m. Eastern time on Friday, one of which, Untapable (by Tapit), stands out so much that she is an odds-on choice at the time of writing.

Having started six times, and won on four occasions (her last two victories came by wide margins), she is owned and bred by Winchell Thoroughbreds and trained by the controversial Steve Asmussen, who is reported to be under investigation by racing officials in Kentucky and New York over allegations of equine abuse in his barn. The Winchell family has been associated with the trainer for 25 years and declined to remove their wards from his barn after controversy ballooned following an undercover "sting operation" by a PETA representative who gained employment in the stable as a groom

David Fiske, racing manager for Winchell Thoroughbreds said of the favourite: "She doesn't really like people that much". In other words, she is intimidating. Whether she will be able to scare her rivals by trouncing them in the race has been put into question after the draw for post positions found her destined to start from the extreme outside spot. Another factor that makes her odds seem niggardly is the absence of a Grade 1 win on her resume.

However, her schooler is bullish: "Her talent level is not in question….It's been a big learning experience for us. We had in our mind where we wanted to put her. We've learned to let her do things as opposed to make her do things." It helps that she has previous experience at Churchill Downs – it is the track where she shed her maiden status on debut last June, and also the venue of her first stakes win, which came in the Gr.2 Pocahontas Stakes over 1-1⁄16 miles in September 2013. Rosie Napravnik will continue her association with the half- sister to Paddy O'Prado.

Perhaps Untapable's chief rival is California shipper Fashion Plate (by Old Fashioned), undefeated at her last three starts, all on dirt at Santa Anita. The 6 to 1 shot from the Simon Callaghan barn is a Gr.1 winner (in the Las Virgenes Stakes), where she defeated Breeders' Cup Juvenile Fillies winner Ria Antonia (by Rockport Harbor), who is also in the field.

Fashion Plate has never been headed in a race since being shifted to the dirt but probably will not have the luxury of an undisputed lead here as a couple of her rivals Sugar Shock (by Candy Ride) and My Miss Sophia (by Unbridled's Song) also have front-running tendencies. Nor has Fashion Plate ever raced outside her home state or been over this trip, which could prove a shade too long. But she does have the wily Gary Stevens guiding her destiny and he is a superb judge of pace.

Rosalind (by Broken Vow) has not done too much winning in her seven race career. A dead-heat in the Gr.1 Ashland Stakes at Keeneland last time out was only the second time the come-from-behind runner had graced the winner's circle and that too she had to share the spoils with Room Service. The Kenny McPeek trainee has been pleasing on the training track, will have regular rider Joel Rosario aboard and is on offer at 8 to 1.

Also at around the same price is Todd Pletcher's  My Miss Sophia, drawn 11. A lightly raced sort, who has only three starts under her belt, she will have to show she is capable of withstanding the commotion of such a big occasion to be a factor. Of her talent, there is little doubt as she is coming off a facile 7-¼ lengths triumph in the Gr.2 Gazelle Stakes at Aqueduct last time out. Javier Castellano gets the call in the saddle.

Ria Antonia has gone down in the record books as the winner of the Gr.1 Breeders’ Cup Juvenile Fillies at Santa Anita last November, when trained by Jeremiah Engelhart. However, that victory came in the Stewards' room, after a nose decision had gone against her on the track. Rested for three months, she might have been a shade rusty when being beaten out of sight by Untapable in her first start of 2014 (she was a never-threatening fourth, over 14 lengths in arrears). However her connections chose to move her West to Bob Baffert in California, where she put up an improved performance when second to Fashion Plate in the Gr.1 Santa Anita Oaks. Here she will be piloted by veteran Mike Smith, and starts at 10 to 1.

Sugar Shock, from the Doug Anderson barn, has local hero Calvin Borel – famous for his rail-hugging victory on Mine That Bird in the Kentucky Derby – in the irons. She has finished first at her last four starts, albeit disqualified once, and has experience – though not a victory – at Churchill Downs. The competition she faces here is stiffer than she has seen at her earlier six starts and she is expected to go off at about 12 to 1. 

British Columbia-based owner-breeder Charles Fipke – truly "Mr. Prospector" – discovered a diamond mine in Canada's Northwest Territories which made him a multimillionaire. Whether his homebred Unbridled Forever (by Unbridled's Song) is also a diamond in the rough will be known after the race. She has certainly displayed encouraging signs of brilliance when annexing the Silverbulletday Stakes earlier this year. Also a 12 to 1 chance, she is a daughter of the 2006 Kentucky Oaks winner Lemons Forever (by Lemon Drop Kid), so is bred for the job. Dallas Stewart conditions the bay, who is scheduled to be steered by Robby Albarado.

Todd Pletcher fields another candidate in the shape of Got Lucky (by A.P. Indy), who will start between her stablemate and the favourite in draw no. 12. Quoted at 20 to 1, she has to make up over seven lengths on form with My Miss Sophia, but with one victory and four runner-up efforts in her five lifetime starts she is nothing if not consistent. What’s more, she has Johnny Velazquez at the controls, has a late turn of foot and could well show significant improvement.

Only one more runner needs a mention. While fifty to one runners are not supposed to win classics, the superbly-bred Aurelia’s Belle (by Lemon Drop Kid) has been quoted too high and will probably start at a shorter price. Like Got Lucky she has never been unplaced from 5 starts and is coming off a success in the Gr.3 Bourbonette Oaks. She ought to appreciate the trip. Channing Hill takes the mount on Wayne Catalano's ward.