Both teams may have come into this match with a maximum 18 points from six matches, but there was little doubt as to who came in as favourites, with Switzerland's goals scored and goals against stronger than Finland's, having racked up two 9-0 wins in the process. And that favourites tag looked well placed just four minutes in, by which time the host nation were already two goals ahead.
The deadlock was broken after just 40 seconds, as Switzerland began the match with a sustained period of attack in the Finnish zone, before Dominik Egli centred from the right side and the puck was tipped into the net by Attilio Biasca.
Finland had only been one goal behind once across the whole championship before tonight, and were stunned to find themselves two down soon after when Tim Berni attacked down the right and saw his shot saved, but the Leijonat couldn't clear the puck, which was picked up by Ken Jager, whose effort struck both the goaltender Justus Annunen and the crossbar on its way in.
The Finns avoided further Swiss punishment after Hannes Bjorninen was called for holding, then early in the second period they held out in defence despite Saku Maenalanen and Henri Jokiharju serving two minutes each, and once back to full strength, the comeback began.
With just over seven minutes to go in the period, Ville Heinola worked the puck out to Jokiharju on the right - he sent the puck towards the near pipe, where it took a couple of deflections before sitting up for Aleksander Barkov to tap home.
Less than three minutes later, the comeback was complete and Barkov was again in the right place to finish the move - he collected Konsta Helenius' pass before taking the puck around the committed goaltender and finishing in style.
Antti Pennanen's side were not able to make the most of an interference penalty against Berni late in the period, then tempers flared in the first minute of the third as Nico Hischier and Aatu Raty were both sent to the box for roughing.
But it was another penalty that ultimately undid the Finnish fightback and set up the Swiss to win - Mikko Lehtonen was guilty of delaying the game with four minutes left, and Jager was again the man to apply the finish on the powerplay less than a minute later.
Damien Riat and Urho Vaakanainen were next to be separated and penalised for fighting, and a sour end to the match from a Finnish perspective culminated with Jager setting up Hischier to make it 4-2 in the final minute and ensure it was Switzerland who topped Group A.
The win and first place for the Swiss means they meet Sweden - who finished fourth in Group B - in the Quarter-finals on 28th May, while Finland play the side who came third in Group B, Czech Republic, on the same day for a place in the last four.
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