As simple as the title have 4 players line up around the circle. When the whistle is blown 2 players enter the ring (circle)drill ends when one the last player is standing in the ring. Players are to check each other no sticks and hands down encourage body contact with circles. Player is out when outside the ring or if both knees touch the ice.

Body contact, knees bent, low body position, hands down

Match players of similar sizes, when more familiar match smaller players with larger players dependning on their physical abilities.