Finland put four goals without reply past Great Britain last time out having already secured safe passage to the Quarter-finals, but Austria - in third place and fighting for their own place in the last eight - were expected to provide stiffer opposition in Zurich.
That looked to be the case as Austria survived an early powerplay following holding from Dominic Hackl, in a tense first period that had just 10 shots on goal in total, but Finland finally found a way through in the 19th minute.
Benjamin Nissner had been called for tripping, and this time the Leijonat didn't pass up the powerplay - a neat turn in front of the net from Aleksander Barkov allowed him to find Mikael Granlund on the right, and he swept the puck home to complete a flowing move.
That goal completely changed the game, as the Finns pulled clear of their opponents in the second period, adding a second goal three minutes in when Waltteri Merala held the puck behind the net before knocking it back to the arriving Saku Maenalanen, who took it in his stride and buried it.
A hooking call against Merala did little to halt the Finnish flow - it was 3-0 in the 12th minute of the period when Jesse Puljujarvi bundled in a rebound after Anton Lundell's strike was blocked, and less than a minute later it was Sakari Manninen's turn to be the rebound scorer after Aatu Raty had a shot saved, as the Finns reached the 40-minute mark 4-0 up.
Austria were on a three-game losing run having begun the championship with three wins, and they finally showed a glimpse of their better selves in the fourth minute of period three, as Nissner found the net shortly after goaltender Justus Annunen lost possession.
But any hopes of an unlikely comeback were stamped out four minutes later, when Vili Saarijarvi and Leni Hameenaho combined for Patrik Puistola to add a fifth for Antti Pennanen's side. Leon Wallner added a late consolation for Austria, but Finland had done more than enough to stay perfect, winning 5-2.
Austria face the United States in their last group match knowing that a loss will leave them needing big favours from elsewhere to hang onto a top four place.
Finland will meet Switzerland in the final match in Group A on Tuesday 26th - both sides have a maximum 18 points from six games, but the Swiss currently lead the group with an incredible +30 goal difference compared to Finland's +22.
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