Sweden were the only team in the 10-team tournament to take maximum points in the Group Stage, winning all four of their Group A matches in Regulation time to earn the number one seed for the Quarter-finals.
That made them strong favourites against Latvia, who had sneaked through in Group B with just one win from four.
But the favourites tag did not weigh heavy on the Swedes, who took the lead in just 10 seconds when Leo Sahlin Wallenius set up Anton Frondell to score after Tre Kronor won the puck back inside the attacking zone following the first Latvian possession.
Sweden then gave Latvia a pair of powerplay opportunities, and though Kristers Ansons equalised on the second of those, parity lasted just three minutes, as Jack Berglund struck to put his side back in front.
The match was all but decided during a 95-second spell in the second period - Sascha Boumedienne found the net 14 minutes in to make to 3-1 to Sweden, then Felix Carell got in on the act to put further daylight between the sides ahead of the final 20 minutes.
Less than two minutes into the third, Frondell was in on the act again, scoring his second of the game. Karlis Flugins pulled one back for Latvia, only for Vaxjo's Sahlin Wallenius to complete his brace and finally end any faint comeback hopes in the final five minutes.
A consolation from Olivers Murnieks made the final score 6-3, long after it was known that Sweden would be moving on to the final four. The four Semi-final teams will be reseeded, thus Sweden will not discover their next opponents until tomorrow.
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