A blow to the heart - Marcel Theroux

The violent death of Daisy's husband leaves her a widow at 32, obliterating everything she has lived for. As she struggles to build a new life, a chance encounter with her husband's killer becomes the starting point of a journey into obsessive hatred. Daisy stalks the man, a small-time criminal and boxer called Joel Heath and pursues him in secret into the twilight world of professional boxing. She befriends Tate, a boxing has-been, and his deaf protege Isaac, in order to strike back at Heath. But Isaac's disability and his once-in-a-lifetime talent present Daisy with harder choices and more dangerous opponents than she could ever have imagined.

This taut intelligent book is a thriller with a brain and a heart.