2-3-2b, 2-5-2 The PlayPics depict contact outside the free-blocking zone. The original contact in PlayPic A is legal (2-5-2). However, the opponent evades the blocker in PlayPic B. In PlayPic C. The block was not continuous and results in a block in the back foul in PlayPic C. If the blocker had maintained contact in PlayPic B the block would have been legal.
2-5-2 Blocking in the back is against an opponent with the initial contact inside the shoulders, below the helmet and above the waist. The penalty for blocking in the back is 10 yards.