It’s Dubai Duty Free Irish Derby weekend but the best three-year-old at the Curragh isn’t lining up in Sunday’s Classic. Instead, the Epsom Oaks heroine Thundering On will try to follow family hoofprints in Saturday’s Group One highlight.Thundering On’s ultra-impressive Epsom performance earlier this month resulted in her achieving an official 119 rating. That’s 1lb more than Christmas Day achieved when landing the Derby 24 hours later. With a sex allowance thrown in, it’s not hard to make an argument for Joseph O’Brien’s filly starting favourite if she were pitted against the colts on Sunday.Since O’Brien has James J Braddock for the Derby, it’s little surprise that Thundering On is kept to her own sex for the Paddy Power Pretty Polly Stakes, albeit taking on older rivals. There may even be a reluctance to have her pigeonholed as a top-flight mile-and-a-half talent.Perhaps most of all, though, is a desire to emulate her dam, Thundering Nights, who won the Pretty Polly five years ago. Also owned by Indian businessman Shapoor Mistry, she had a single foal before dying of colic. But what a talent that foal has turned out to be.Stepping up from victory in the Salsabil Stakes – named after a filly that won the 1990 Irish Derby – Thundering On outclassed her Oaks opposition in a manner rarely seen. Dylan Browne McMonagle brought her from last to first on soft ground and she sped past Legacy Link.The latter didn’t boost the form at Royal Ascot but there were excuses for her effort. What remains is the impression left by the winner, who takes in the Pretty Polly en route to next month’s Oaks back at the Curragh.“The Irish Oaks is the race we’re very keen on, we want to have her at fever pitch for that, but I quite like the look of the Pretty Polly on the way there in terms of timing. I think 10 furlongs is a lovely trip for her and I think the Curragh will be a good track for her,” O’Brien said.Ryan Moore on Sun Goddess wins The Revamp Conservation And Restoration Irish EBF Fillies Maiden at the Curragh on May24th, 2026. Photograph: Morgan Treacy/©INPHO Thundering On is one of two three-year-olds taking on seven senior rivals. Whirl won the Pretty Polly last season, ending a streak of five victories in a row for older horses. Clearly the best of the “oldies” this time, on figures at least, is the English challenger Estrange.Her trainer David O’Meara will hope for an ease in ground conditions as the recent warm-weather conditions are forecast to break this weekend. The grey returned to action with a smooth success at Carlisle last time.Estrange creditably mixed it with a top filly in Minnie Hauk last season but may not have things any easier against Thundering On. Quick going shouldn’t be a problem to the O’Brien filly, whose mother won the Pretty Polly on good to firm.Royal Ascot juvenile from will get a quick test during Saturday’s Curragh action as Aidan O’Brien wastes no time keeping some high-class two-year-olds busy.Sun Goddess started odds-on for the Albany at Ascot but couldn’t resist a late thrust by Libertango. Before that she had beaten Green Express by five lengths at the Curragh. The latter is opposing again in the Group Two Airlie Stud Stakes, which is interesting considering she looks a maiden winner in waiting.But when O’Brien gets aggressive with his juveniles it usually pays to stay onside with them.[ Racing’s written rules overlooked far too frequently in favour of unwritten onesOpens in new window ]The same comment could apply to Confucius when he lines up in the Group Three Jebel Ali Anglesey Stakes. He started favourite for the Coventry, and was Ryan Moore’s pick over Great Barrier Reef, but still could manage only sixth to his stable companion. There didn’t appear to be any excuses, although the expensive purchase could prove a very different proposition here.Saturday’s “Derby” is the ladies’ variety and ground conditions can favour Diamond Exchange enough for Jessica Harrington’s runner to score. The trainer also looks to hold good claims in the concluding maiden through Suspicious Mindz.