Mars didn't waste much time in producing all the offense it needed to get a chance to defend its WPIAL Class AA boys' soccer championship.

Try 48 seconds.

Chris Karns scored less than a minute into the game and the reigning champion Planets (20-1) added two second-half goals to coast to a 3-0 semifinal win against Chartiers Valley (12-6-2) at North Allegheny.

Yulian Lutsiv and Michael Page also scored for the Planets, who have won 17 games in a row.

Rob Sigurdsson earned his fifth consecutive shutout and ninth in the past 10 games.

• Greensburg Central Catholic 1, Seton-LaSalle 0: Tim Wood's goal with 18 minutes left helped the Centurions (17-4) knock off the defending WPIAL and PIAA champion Rebels (14-7) at Shaler. Wood's goal, his 24th of the season, came off a corner kick by Ethan Shula. The Centurions' goalkeeper, Nick Draghi, made 17 saves.

"This is the best I've seen Nick play," said Centurions coach Tom Kennedy. "This is his first year of playing soccer. I'm glad we talked him into playing."

• Springdale 2, Freedom 1: The Dynamos (15-1-3) followed up a scoreless deadlock at the intermission by tallying the first two goals of the second half and held on to defeat the Bulldogs (15-3-1) at North Allegheny. Ryan Francis played a hand in both goals, scoring off a give-and-go from Bryan Weimerskirch 19 seconds into the second half and later booting a corner kick that led to Mike Funyak's goal. Brad Prinkey scored with eight minutes left for Freedom, which hit the crossbar with a shot in the closing minutes. The Dynamos are riding an 18-game unbeaten streak.

• The top seed in all three classes advanced to tomorrow's WPIAL girls' volleyball semifinals with quarterfinal victories last night. Mt. Lebanon, the top seed in Class AAA, earned its third consecutive semifinal berth with a 3-1 victory against No. 8 seed Shaler. West Allegheny, the top seed and defending champion in Class AA, earned its fifth consecutive trip to the semifinals, with a 3-0 sweep of No. 9 seed Derry. West Shamokin, the top seed in Class A, recorded a 3-2 victory in its quarterfinal match against No. 9 seed North Catholic.

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