Not good. I went to the barn last evening to do some groundwork with Rugby and he was unsound. I tried lunging him and he was short striding and seemed sore up front and it would come and go. He didn't want to do anything more than walk and when I asked him to jog just to see if it was worse he was especially aggravated when moving to the right. I stopped him and brought him back inside.
I called the vet today and he checked Rugby out. It's definitely his right front. He didn't respond when his hoof was tested, there are no signs of heat, swelling or elevated pulse but showed improvement when nerve blocked. The vet diagnosed it as a heel pain condition but could not give a definitive diagnosis based on that alone.
He noted that when we X-rayed Rugby for the pre-purchase exam a year ago, there was no indication of navicular disease at that time. He suggested bute and isoxaprine as starting therapy to see if it would alleviate his discomfort. He also suggested egg-bar shoes to give him relief but I asked to hold off on that until we pull some X-rays of that foot since he's currently barefoot and would need to be barefoot for the X-rays. I figure at least we can compare to last year's pictures of that hoof and rule out things or find an answer by comparison. The vet agreed so tomorrow he'll be X-rayed.
So I'm trying to stay calm until we know more.