Clearly the last shot was square on the balls (the first three being borderline low as Kov said).
Just notice Kov's bum jolting back; that's definately not a body shot. As someone said, it looked more like resignation and I think it's because of all the stuff Ward was getting away with. (One of the first low blows he complained about was just laughed off by the ref).

I think ward seemed to be getting an edge during those rounds anyway.