Few arriving at Swiss Life Arena would have been expecting anything other than another win for the hosts - Switzerland topped Group A having won all seven of their matches in regulation time, scoring 39 times, while Sweden beat Slovakia in their final Group B match to sneak into the top four.
But the home fans were silenced in the seventh minute, when Linus Karlsson fought hard on the left of the attacking zone to maintain possession before working it across to Oliver Ekman-Larsson, his lay-off found Emil Heineman, and his centre found Karlsson with space and time to fire home.
Things got worse for Switzerland just seconds later when Dean Kukan was penalised for cross-checking Ivar Stenberg. Sweden thought they had capitalised on the powerplay, but Oskar Sundqvist's goal was disallowed after review for being diverted in off his skate.
Swiss fortunes seemed to be turning as they survived five minutes a man down before finding an equaliser in the 14th minute, when Denis Malgin collected a rebound and set the puck back for Roman Josi to strike from distance straight into the top corner.
That goal was the springboard for Switzerland to go into the second period and hit their usual heights - they held out through another Swedish powerplay after a tripping call against Calvin Thurkauf before taking the lead in the 13th minute.
Roles were reversed as Josi slipped a pass through to Malgin, for whom the opposition defence parted like the Red Sea, as he crossed the blue line and carried on unchallenged before powering the puck past Magnus Hellberg.
Discipline failed to improve soon after as Timo Meier was given just two minutes for cross-checking, as was Albert Johansson for his retaliation, but then it was Tre Kronor who went a man down in the final five minutes as Joel Persson was called for tripping.
And just over a minute later, Die Nati made use of the powerplay, as Nico Hischier weaved his way delightfully through the defence on the left, cutting back inside to play the puck across for Thurkauf, whose shot had just enough on it to beat Hellberg.
A strong hit from Meier on Sundqvist went unpunished despite ending the Swede's evening, but when Switzerland were penalised either side of the second break, Sam Hallam's side still couldn't work a way back into the game.
Having only had three shots on goal in period two compared to Switzerland's 12, Sweden were more productive in the final period, leading the shot count 9-7, but that wasn't enough to eat into the Swiss lead, and the hosts held on for a 3-1 victory.
The Swiss march on to the Semi-finals, which will be played on 30th May, while Sweden are left to dwell on a regression from last year's bronze medal finish.
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