MONROEVILLE — Mars soccer and the WPIAL Finals are getting used to each other. The Planets’ boys and girls varsity squads reached the Class AA championship round by posting 2-1 semifinal victories over Belle Vernon Wednesday night at Gateway’s Antimarino Stadium. The boys joined the championship round for the fourth time in five years when junior forward Matt White snapped a 1-1 tie with his 18th goal of the season with 5:26 remaining. Senior captain Spencer Posey — who scored the game’s first goal with 23:23 left in the first half — fed the ball ahead to White for the game-winner. “It was a perfect lead from Spencer,” White said. “The ball left my foot and went off the goalkeeper’s knee ... It bounced back to me and I was able to chip it over him.” White lofted his shot high in the air. The ball bounced a couple of times and rolled into the left corner of the net as Belle Vernon goalkeeper Alex Robinson was unable to get back into the play. Posey’s goal was his 31st of the campaign. He rifled a shot off the inside of the left post from point-blank range. The ball ricocheted off the right post as well before going in. Mars’ girls (18-1-1) have lost just one game over the past two seasons and are bidding for their third consecutive WPIAL title. “I like our talent, but weather is the big equalizer in soccer,” Mars girls coach Blair Gerlach said. “With the rain and the wind, we really couldn’t play the style of game wewanted.” The Planets took a 1-0 lead with 23:01 left in the first half when Lydia Dennis broke in free down the right side and dribbled a shot past goalkeeper Ashly Gagliardi. The tally was her 29th of the year. Karli Paracca gave the Planets a 2-0 edge with 14:09 remaining, warding off two defenders before sliding her 34th goal of the season into the net.