feel for you GD, my eldest whippet lost the site in his right eye from a blackthorn, he kept the eye but it is good for nothing. Although, it will no doubt hinder him in the field they do adapt suprisingly well. my dog still catches well (not as good as before albeit but still pretty good). As has been said it is frustrating when they put in a good run then get blind sided by their quarry but he will adapt as will you in the way you work him. my advice would be to rest him well and then get the most you can out of him and when your out with your mates tell them his catches count for double! ;-