Secretariat's Historic Belmont Stakes: Field Size and Reasons

Question
In the 73 Belmont that Secretariat won by 31 lengths, how many horses were in the field and if it is a low number, why were there so few as compared to a race like this years Derby which had at least 15?
Thanks

Answer
Terry -

It was a 5-horse field - Secretariat, Twice A Prince, My Gallant, Private Smiles, and Sham.  The field was so small mostly because Secretariat and Sham had already finished 1-2 in both the Derby and the Preakness, with the third horse far behind Sham in both cases.  The two big horses simply scared the others away.  It was a great race - one I'll never ever forget.

I hope that helps.

- Mark Shrager