The only time mine run like that is when they hear or see the BUNNY! (lure).
I race my Greyhounds and Borzoi at NOTRA (amateur oval track racing) meets at the practice track in Jacksonville
I did own a racing Greyhound pup, but she died at the training farm unexpectedly and for no known exact cause. We think a reaction to a dewormer, though she'd had the same dose before with no problem. She was a Dodgem By Design daughter out of a WW Applejax brood.