| Kentucky Derby | |
| Grade I stakes race | |
| Location | Churchill Downs, Louisville, Kentucky |
|---|---|
| Date | May 6, 1978 |
| Winning horse | Affirmed |
| Jockey | Steve Cauthen |
| Trainer | Laz Barrera |
| Owner | Harbor View Farm |
| Conditions | Fast |
| Surface | Dirt |
| Attendance | 131,004[1] |
The 1978 Kentucky Derby was the 104th running of the Kentucky Derby.[2] Affirmed, under jockey Steve Cauthen, won the race by 1 1/2 lengths over Alydar.[3][4] Believe It finished 3rd, 1 1/4 lengths behind Alydar, and 30:1 longshot Darby Creek Road finished 4th.[5][6] Affirmed won the Triple Crown by defeating Alydar by decreasing margins in the Preakness Stakes and the Belmont Stakes.[3]
11 horses competed in the race.[3] Alydar went into the race as a 6:5 favorite, despite Affirmed having won 4 of the 6 previous races between the two.[3] Affirmed went off at 9:5.[3] Sensitive Prince and Believe It were the only other horses to go off at less than 30:1, at 9:2 and 7:1 respectively.[5] Sensitive Prince and Affirmed, both frontrunners, were near the lead early in the race behind long shot Raymond Earl.[5] Sensitive Prince took the lead at the first turn, but Affirmed gained the lead at the second turn.[2] After attaining the lead, Affirmed held it for the remainder of the race except for a brief moment when Believe It led by a head.[2][6] Alydar charged from the outside down the stretch, and overtook Believe It, despite the two horses bumping, but Alydar could not overtake Affirmed.[2][4][6]