Most likely what hit Poznanski in the third period was the message sent by being on the receiving end of a very dominant, two-minute second-period rideout, and the energy expended trying to escape it. Likely a brand new experience for the veteran, especially when considering it was laid on him by a redshirt freshman.
Had to chuckle after reading Goodale's pre-match comment, presumably experience-based, that Poznanski was "at his best" in situations where he had nothing to lose -- implying such would be the case in his match with Barr. Assuming the head coach actually had any idea what he was talking about when he chose to make that comment, we can only wonder if there might be words in the English language, any words at all, adequate to describe what Poznanski's "worst" might look like.