Aidan O’Brien is confident Santa Barbara has not yet reached the ceiling of her ability ahead of her second tilt at classic glory in the Cazoo Oaks at Epsom on Friday.

A half-sister to a pair of Breeders’ Cup winners in Iridessa and Order Of Australia, the daughter of Camelot made a big impression when winning on her racecourse debut at the Curragh in September.

Few could have envisaged at that stage she would go off joint-favourite for the 1000 Guineas at Newmarket on just her second career start, but unusually bullish reports of blistering workouts on the Ballydoyle gallops in the spring saw her price collapse.

Santa Barbara’s supporters were ultimately left counting their losses after the first fillies’ Classic of the season over the Rowley Mile, but she emerged with plenty of credit in finishing fourth and O’Brien has certainly not lost the faith.

O’Brien said: “Santa Barbara is very well. She came out of Newmarket like I hoped she would and everything has gone well since then with her.

“We trained her for Newmarket like it was her first run of the season and we had to be careful. This time we got to train her for a classic.

“She did very well in Newmarket for a filly only having her second run. She was always very special in her work.

“She ran a big race and showed what she can do. When the ground is quick at Newmarket, it just makes it a little bit more tricky for horses with not a lot of experience. We were delighted with the way she travelled and she showed us the class that she shows us at home.

“It is a risk going into a classic on only your second run, from a very easy run on softish ground at the Curragh to then go to Newmarket on fast ground. We were really delighted the way she came out of it.

“The Guineas is the Guineas, but you would imagine normal, natural improvement will come. She hasn’t shown us anything in her work to suggest otherwise.”

FIVE RUNNERS

Santa Barbara is just one of five runners for O’Brien, who has already won the Oaks on eight occasions.

Snowfall is another leading contender, having made a successful start to her campaign with a front-running victory in the Musidora Stakes at York. With Ryan Moore siding with Santa Barbara, Frankie Dettori comes in for the ride.

O’Brien added: “Snowfall is good. We always thought the world of her last year, which is why we campaigned her in such good races.

“She was probably a little bit weak, but she’s bred to be a classic filly and is bred like a filly that could get the trip.

"She wintered very well and Ryan was delighted with her at York.”

Divinely, Willow and La Joconde complete the Ballydoyle quintet. Divinely only finished fourth in the Lingfield Oaks Trial, but has been a significant market mover this week.

“Divinely had a lovely run in Lingfield, probably a lot better than it looked. Ryan was over the moon with her. They went slow, which didn’t suit, but Ryan was delighted with her. Since then all the numbers on her work have been very good.

“All her figures from her works have been coming out very high – that’s usually a very good sign.

“Willow ran in Naas and we think she has progressed nicely. She progressed a lot from the first to Naas and we think she has progressed again.

“We always thought La Joconde was better than she has showed on the track. She hasn’t won her maiden yet, but has always worked a lot better than a maiden.