Nomsa, while playing a game of netball, was struck on the head by the ball. As a result of this, Nomsa sustained a serious head injury. It transpired that her fellow player Kefilwe had attempted to shoot the ball into the goal ring but missed. The ball subsequently struck Nomsa's head. Nomsa would like to institute a delictual action against Kefilwe for the head injury she sustained. Discuss with reference to authority, which ground of justification Kefilwe may rely on as well as the likelihood of it succeeding.