The boy’s state high school soccer tournament opens today in Muscatine with quarterfinal round in action in both classes. In 1A, Davenport Assumption opens against Sioux City Heelan. The Knights will be in search of a second straight championship. Assumption coach Dave Kraxner says the tournament format puts a premium on conditioning. Kraxner says he knows little about Heelan’s style of play so the Knights will focus on how they would like the game to be played.Sioux City North is in the class 2A field for the third consecutive season and opens tonight, against Cedar Rapids Washington. North coach George Tsiobanos expects a difficult matchup.Tsiobanos sas the three-games-in-two-days format makes it a grueling run to the title.Championship games in both classes are tomorrow afternoon.