The daughter of Camelot is the general 6-4 favourite for the fillies' Classic, despite having only won a backened maiden in the mud at the Curragh last season. She had been quoted at 33-1 after that success.
Santa Barbara's reputation has soared in recent weeks, with O'Brien issuing several glowing bulletins. She will be ridden by Ryan Moore at Headquarters with Frankie Dettori snapped up to ride the trainer's second representative in Mother Earth.
One significant obstacle removed from their path on Friday was Fillies' Mile winner Pretty Gorgeous, trained by Aidan's son Joseph. She will not take part because of a dirty scope.
A final field of 12 has been declared.
Mother Nature has the stronger form claims of the o'Brien Sr pair after being placed in the Fillies’ Mile and Breeders' Cup Juvenile Fillies Turf but it is undoubtedly Santa Barbara who carries most stable confidence with O'Brien suggesting she has been top of the pecking order at Ballydoyle since last year.
“The plan at the moment is for Mother Earth and Santa Barbara to run," O'Brien said in a webinair hosted by Newmarket Racecourse and QIPCO British Champions Series. "It was a very nice run from Mother Earth in the Fillies’ Mile last year and Santa Barbara has obviously only had one run, but we have always thought a lot of her.
“We didn’t want to over-race Santa Barbara and obviously it is a big call for her, but she seems to be in good form. She always looked very special and of the two year old fillies last year was always top of the pecking order.
“She only had the one run but on her home work was always very impressive and looked exceptional. She is a very strong traveller through a race and a big powerful, strong filly. Two of her siblings (Order Of Australia and Iridessa) are Breeders’ Cup winners and so all that adds up together."
He added: “It will only be her second run and on quickish ground, so she will still be green and it will be interesting to see how she copes with it all. You would imagine she will learn a lot from it. It will do her no harm.
“To have had another run might have been an advantage, but she is a quick learner and very intelligent.
“She was always very highly thought of here and won her maiden very easily. She has done well over the winter and her work through the Spring has always been very, very good. Anything she works with, she always looks to be going easiest – no matter what horse. She hasn’t been asked to see how much is in there but she has always looked to be dominating anything we have worked her with.
“It will be interesting to see what happens when she does come off the bridle, which will happen in the Guineas.
“Ryan (Moore) will ride Santa Barbara with Frankie on Mother Earth. You have to respect all the trial winners, although most of the trials take place over seven furlongs and it is interesting to see how they cope with the extra furlong."
O’Brien is seeking a seventh 1000 Guineas success. The record for a trainer is nine wins, achieved by Robert Robson.
Jane Chapple-Hyam has never been afraid of a challenge and in Saffron Beach she has a genuine live chance in Sunday’s contest.
Unbeaten in two runs as a juvenile, including success in the Oh So Sharp Stakes, she looked sure to be suited by stepping up to a mile when second on her return in the Nell Gwyn, finishing behind the reopposing Sacred.
“From all accounts Adam (Kirby) was happy with her last time,” said Chapple-Hyam. “It was a trial and he feels she was strong at the line and took a fair bit to pull up. With that in mind, we’re really looking forward to running her over a mile.
“Once the winner had flown a bit, Adam wasn’t too hard on her, so she had a good experience and didn’t have too hard a race. She wouldn’t have been fully wound-up there, either.
“She had a good experience. It was her third time on the track which can count for a lot in the Guineas, she picked up some more black type – which is important – and we’re looking forward to Sunday, when hopefully she can pick up some Group One black type.”
Given the positive reports from O’Brien about the favourite, Chapple-Hyam feels if they are correct, Santa Barbara could be a new superstar.
“Aidan’s no fool. If he feels she’s been galloping well against colts, that just says it all. Good fillies can go by colts,” she said. “If she’s as good as that, then we might have a new Enable on the scene.”We've teamed up with the Flat experts at Timeform to bring you a FREE copy of their latest book - 50 Flat Horses to Follow throughout the 2021 season. Click here to claim yours for FREE!
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