Juddmonte Irish Oaks 2026: The Curragh Preview, Contenders and Ante-Post Odds

Saturday 18 July brings one of the season’s most compelling fillies’ races to The Curragh. The Juddmonte Irish Oaks, worth €500,000 in prize money, is a Group 1 contest run over 1 mile and 4 furlongs for three-year-old fillies. Post time is 16:10 local. Going is reported as firm as of 9 July, with watering in progress.

Final declarations are due on Tuesday 15 July. There are 65 runners at the Stage 1 entry stage, so the field will thin considerably. Jockeys listed below are pending confirmation at declarations.

The Race Context

The Irish Oaks sits at the heart of the European fillies’ Classic programme. It follows the Epsom Oaks (run 5 June at 1m4f) and offers horses beaten, placed or unplaced at Epsom a second shot at Classic glory, while others who bypassed Epsom entirely come in fresh. This year, the race draws in runners from France, Britain and Ireland, giving it a genuinely international feel.

The Curragh’s middle track at 1m4f is a stern stamina test. Firm going will favour those with a clean, efficient action rather than horses who need dig in the ground. A cough scare in one camp and stamina questions over two others add layers of uncertainty to what looks, on paper, a wide-open renewal.

Key Contenders

Thundering On (Joseph Patrick O’Brien; likely Dylan Browne McMonagle; 2/1 ante-post)

The Epsom Oaks winner heads the market on the strength of a four-length beating of Legacy Link at Epsom on 5 June. That performance was authoritative. The step back to 1m2f for the Pretty Polly Stakes (Group 2, The Curragh, 27 June) did not suit: she finished fourth, beaten 2.5 lengths by older fillies. O’Brien’s camp reported a cough in the aftermath, though she has since been given a clean bill of health.

If the Epsom form is as good as it looks and the Pretty Polly run was an anomaly, she arrives here as the rightful Oaks favourite. The question the market is pricing at 2/1 is whether the cough knocked her off course, or whether the drop in trip and step up in class simply found her out that day.

Form: 6042-21

Earth Shot (William Haggas; likely James Doyle; 2/1 ante-post)

Owned by Wathnan Racing and trained by William Haggas, Earth Shot bypassed Epsom entirely and won the Ribblesdale Stakes (Group 2, Royal Ascot, 18 June, 1m3f212y) by a head from Johanna Walsh. Haggas has said bluntly: “She’s a mile and a half, three-year-old filly.” That is as clear a trainer flag as you will get.

Joint favourite at 2/1 with Thundering On, she is the only runner who arrives having won over a distance close to 1m4f since Epsom. The slight reservation is that she won narrowly and has Johanna Walsh behind her rather than a deep field. Still, she is unbeaten in terms of Oaks-trip form and Haggas does not overstate horses.

Form: 192-12BF

Diamond Necklace (Aidan O’Brien; likely Ryan Moore; 5/1 ante-post)

The French raider arrives with an unbeaten record across five races and genuine Classic credentials: she won both the Poule d’Essai des Pouliches (French 1,000 Guineas) and the Prix de Diane (French Oaks, Chantilly, 14 June, 1m2f) at 4/9 in the market. Aidan O’Brien says she “really quickens well”, which is a quality that will be tested over the extra two furlongs here.

The Racing Post has flagged a market doubt over her staying 1 mile 4 furlongs. The Prix de Diane is run over 1m2f, not 1m4f, so she has never actually been tested at this distance. She is unbeaten, but unbeaten at up to 1m2f. Whether that finishing kick translates to staying power at Classic distance is the question at 5/1.

Johanna Walsh (Joseph Patrick O’Brien; likely Dylan Browne McMonagle; 4/1 ante-post)

A second string for the O’Brien yard, Johanna Walsh was beaten a head by Earth Shot in the Ribblesdale at Royal Ascot. She had previously won a maiden at Leopardstown over 1m2f. There is a case that she ran right up to her level at Ascot and arguably the nose gap flatters Earth Shot.

At 4/1, she is a more attractive price than Earth Shot for the same form at almost the same race. The complication is that O’Brien likely saddles Thundering On as first choice, which may affect race tactics if both line up.

Form: 303-31

Legacy Link (John and Thady Gosden; likely Colin Keane; 12/1 ante-post)

Legacy Link was second to Thundering On at Epsom, beaten four lengths, and earned an RPR of 125. That is a solid mark. She represents the John and Thady Gosden yard and Colin Keane, who has strong Curragh form, is likely to ride.

At 12/1, the market is saying the Epsom gap is genuine and unlikely to close. That may well be right. But form at the same distance and track configuration makes her worth including in any analysis.

Form: 38314-12

Precise (Aidan O’Brien; likely Wayne Lordan; 16/1 ante-post)

The Irish 1,000 Guineas winner from The Curragh (24 May, 1m), Precise beat True Love by 2.5 lengths over a mile. She has never run beyond 1 mile. The Racing Post has a stamina concern on record. At 16/1, the market is reflecting exactly that doubt. This is a form horse who needs to prove she stays.

Amelia Earhart (Aidan O’Brien; 6/1 ante-post)

Disappointed in the Epsom Oaks, having shown earlier form that marked her as a contender. At 6/1, she is priced as a horse the market respects more than her Epsom run suggested it should. A return to form at The Curragh is possible.

Form: 4241-16BF

Betting View

Ante-post prices from Paddy Power, correct at time of writing:

The market is essentially split between Thundering On and Earth Shot. Both have legitimate claims. The Epsom form says Thundering On is the best three-year-old filly in training at 1m4f. The question is whether the Pretty Polly and the cough scare have disrupted her preparation enough to let a fresh, unexposed horse past her.

Earth Shot’s trainer has said she is a mile-and-a-half filly. That is a direct statement of confidence about the distance. She arrives having won over close to that trip. Whether she can beat a fully fit Thundering On is the crux of the race.

Diamond Necklace at 5/1 is the most interesting outsider from a form perspective, but she has never been asked to stay 1m4f. A genuinely fast-ground test at The Curragh may suit her finishing kick, or it may expose a stamina ceiling.

These are ante-post prices and will move between now and declarations on Tuesday 15 July. Non-runner/no-bet terms are available with most bookmakers ante-post.

Conclusion

This looks like a two-horse market that has legitimate grounds to remain a two-horse market. Thundering On is the Epsom Oaks champion and holds the strongest form at the distance. Earth Shot is the freshest Haggas filly the trainer rates as a mile-and-a-half horse. Between them they cover the most likely outcomes.

Diamond Necklace adds an element of risk. She is unbeaten and trained by Aidan O’Brien, who wins Irish Oaks. The stamina question is real and unresolved. Johanna Walsh was only touched off at Ascot and at 4/1 represents better odds than Earth Shot for very similar form.

Final declarations on Tuesday 15 July will sharpen the picture considerably. Jockeys, weights and the size of the final field will all matter. Watch for any market moves when declarations are published.