The horse race (puzzle #03)

Puzzle time!

This one took me more than 3 days to solve. I hope youbwill solve it faster! Oh, i forgot to mention that this puzzle and the other 2 are from "The Big Book of Puzzles".

Difficulty: :star2: :star2: :star2: :star2: :star2:

For a hint, coment "H"

The puzzle:

"The will of an eccentric character stipulated that his two heirs had to run in a horse race, and the owner of the last horse would return the heritage. At the agreed time, the race takes place, but the two heirs do not urge their horses to move. To make things right, the executor made a small change in the race. According to this change, the race of the two horses was resumed and the one who finished first won the legacy.

How could this have happened, even though the will was respected?"

Good luck everyone! Bye!