from Kerry Fraser of TSN,

A player is not allowed to "make himself bigger" with the use of his stick and/or hands to detain or restrain an opponent as you describe in your question. Should this occur, it is a clear violation of Rule 56 and should be penalized as interference. At training camp in September, the referees were instructed to apply a strict standard with regard to interference of this nature once the puck was chipped past a defender. The mandate was put forward to allow attackers clean and legal access to pursue the loose puck and generate offence.

There are legal methods available for a defender to delay, contain, or even eliminate an attacker with contact through establishing proper "body position." Body position is determined as a player in front or beside an opponent, traveling in the same direction. A player is allowed the ice he is standing on (body position) and is not required to move in order to let an opponent proceed. A player may "block" the path of an opponent provided he is moving in the same direction. Moving laterally and without establishing body position, then making contact with the non-puck carrier is not permitted.

The key to legally detaining an attacking player who has chipped the puck past a defender is for that defender to immediately turn and skate in the same direction as the attacker. If executed properly, this considerably lengthens the distance his opponent must travel to get where he is going (to the puck). The defender must keep his feet moving in the same direction as the attacker and attempt to take the ice away as he moves forward.

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