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Mark Lazerus on Twitter: “Toews said the Blackhawks are still in “shock.” Said there was no point at which they expected to lose the series.”(r/hockey)
Ken Dryden, goalie for the Canadiens through most of their winning streak in the 70’s, wrote quite a bit about exactly this. I’d say about half of his book, The Game, really goes into the mental struggles a winning team endures.
I’d encourage any hockey fan to read it, but to summarize, Dryden talks about how impossible it is to play at your top level endlessly. He could see the Islanders threatening to overtake them if they let off the gas even a little, and knew that inevitably that is precisely what would happen. He could see his backup suiting up every night, waiting for him to make a mistake. The pressure – pure, internal, mental pressure – was exhausting.