| Understated | Saint-Cloud,
27-Oct-24 |
| Understated | Fairview,
28-Jul-23 |
| Understatement | Morphettville Parks,
08-Jun-24 |
| Understudy | Deauville,
17-Aug-25 |
| Understudy | Geelong,
05-Jun-25 |
| Understudy Kitty | Delaware Park,
14-Aug-25 |
| Undersupervision | Cheltenham,
16-Apr-25 |
| Undertaker | Muswellbrook,
24-Oct-17 |
| Undertaker | Keeneland,
12-Oct-25 |
| Undertheblackberry | Warrnambool,
15-Jun-10 |
| Underthebonnet | Eagle Farm,
21-Dec-11 |
| Underthemistletoe | Aquis Park Gold Coast,
22-Sep-18 |
| Underthemistletoe | Belmont At The Big A,
20-Oct-24 |
| UNDERTHERADAR | TE R,
28-Oct-13 |
| Underthespotlight | Mount Isa,
11-Aug-22 |
| Undertone | Delaware Park,
10-Oct-25 |
| Undertow | Mountaineer,
31-Jul-25 |
| Undervalued Asset | Belmont At The Big A,
29-Oct-23 |
| Underverse | Armidale,
18-Mar-24 |
| UNDERWATER | Ferguson Park,
03-Apr-10 |
| Underwood | Royal Randwick,
04-Sep-21 |
| Underworld | San Isidro,
25-Jul-24 |
| Underworld | Greyville,
05-Jul-25 |
| Underworld Goddess | Los Alamitos Racecourse,
12-Oct-25 |
| Underwriter | Deauville,
15-Aug-25 |
| Undetected | Mountaineer,
26-Oct-23 |
| Undia Candy | San Isidro,
01-May-25 |
| Undici | Penn National,
19-Jul-25 |
| Undisclosed | Belmont,
08-Aug-20 |
| Undismayed | Horseshoe Indianapolis,
19-Oct-23 |
| Undismissable | Glen Innes,
13-Jan-24 |
| Undisputable | Sandown Hillside,
03-Sep-25 |
| Undisputable | Ellis Park,
24-Aug-25 |
| Undisputed | Cranbourne,
29-Mar-24 |
| Undisputed | Belmont At The Big A,
06-Oct-25 |
| Undisturbed | Benalla,
23-Mar-24 |
| Undisturbed | Santa Rosa,
06-Aug-23 |
| Undivided | Hawkesbury,
25-Jun-24 |
| Undo The Right | Sam Houston Race Park,
06-Apr-25 |
| Undolla | |
| Undone | Huntingdon,
01-Apr-24 |
| Undoubtable | Port Augusta,
02-Sep-18 |
| Undoubted | Home Hill,
08-Jul-23 |
| Undoubtedly | Horseshoe Indianapolis,
13-Jul-23 |
| Undress | Tampa Bay Downs,
06-Jan-24 |
| UNDUE | Allan Scott Park Morphettville,
11-Jun-11 |
| UNDUE POWER | |
| Undulate | Saga,
10-Aug-24 |
| Une Autre Belle | Morioka,
10-Oct-23 |
| Une Aventure | Deauville,
24-Oct-25 |
| Une Brise | Saga,
13-Oct-25 |
| Une Davrill | Compiegne,
23-Apr-24 |
| Une De Bonneveine | Marseille Midi,
15-Mar-24 |
| Une De La Seniere | Ludlow,
04-Nov-22 |
| Une De Mai | Chantilly,
18-Mar-24 |
| Une De Mai | Fort Erie,
02-Sep-25 |
| Une Etoile | San Isidro,
01-May-24 |
| Une Etoile | Nakayama,
15-Jan-23 |
| Une Fragrance | Le Mans,
29-Oct-25 |
| Une Gravure | Saint-Cloud,
09-Oct-25 |