He wore vest under his shirt during the Wimbledon Final when it was really hot. We know for a fact that Andy has a long term back problem. I think he will be wearing a vest for now on to help with the back. The back problem will never go away and it did not stop him from winning Wimbledon.
yes an ongoing back problem, which is aggravated by playing on clay. Hadn't noticed the vest at W final must admit so I guess you're right on that one. Anyway the hope is that it's ok at present given he's opted to play all 3 matches, if necessary.