Small dog warning

This may have been on here somewhere before and I apologise if it has but it happened to us yesterday so thought I'd mention it. We have been warned and heard a couple of horror stories regarding re- homed greyhounds and their liking of small dogs, well we  met it 1st hand as out walking our small  (white ) dog. Nobody was around as we walked across a field with a pathway through it so let our dog off the lead to stretch her legs, we were hovering quite close in case nature took its cause and luckily turned around to see a greyhound running at full speed towards us from the other side of the field. Molly (our dog) looked up and seemed rooted to spot which was fortunate as oh managed to pick her up as this dog flew up at him, he is 6ft 4 and held her up ending up quite heavy handedly shoving the dog off him twice. On the 2nd shove the dog fell away then bounded across the field to the owner.  5 minutes later the dog again does the same thing, we never confronted the owner as she was still some way away and we were glad to just get away and home. These dogs are trained to chase fluffy things around tracks and in some cases fields. If you have a small fluffy dog (as ours is) please beware and on your guard. They are trained this way it is instinctive and we dread to think what would have happened if Molly had bolted before she was picked up. we have heard the warnings before and now seen it 1st hand, this is just to alert people to the possible chance of it happening, not a gripe against greyhounds, we are both dog lovers, this is what they are trained to do.