After a solid regular season, the Swampscott boys tennis team (12-3) is set to open the Division 3 North state tournament this Saturday at home (4 p.m.). Seventh grade standout Matt Jacobs leads the 5th seeded Big Blue into play against 12th-seeded StonehamJacobs will be the No. 1 singles player for coach Andrew Turchon, after finishing the season with a 10-2 record.”He’s a young kid, but he’s very confident, but humble at the same time,” said Turchon. “He doesn’t look over the net and think he’s already won, but he plays a smart game, which gives him the chance to win.”Turchon’s first doubles pairing of senior Josh Lunder and sophomore Sam Crimmins finished the season at 13-2.”They play a really strong and aggressive game, and have done great together all season,” said Turchon.Turchon has stressed to his team the importance of not overlooking the Big Blue’s opponent.”I don’t know much about Stoneham but I know they’re a lot better than their record shows,” he said. “The Middlesex conference is a tough one, so we’re not going to overlook them.”The Big Blue are 6-1 on their home court this season.Ninth-seeded St. Mary’s (8-8) won four straight matches down the stretch to reach the state tournament in a season deemed “surprising” by coach John Wynne.”When we were 4-8, we realized in order to make it here, we had to win four straight matches,” he said. “It was tough but the kids made it happen. It really brought them together as a team.”Junior captains Grant McKinnon and Dennis Bertocchi lead a young team, which lost seven seniors last season, five of whom were starters.The Spartans’ opponent, No. 8 Newburyport, figures to be a tough matchup, according to Wynne.”They come from a strong league that produces a bunch of good teams, so we’re expecting a very tough match,” he said. “We were able to pull off four straight wins though, so why not five?”Division 1 NorthSecond-ranked St. John’s Prep (16-1) earned a first round bye and awaits its quarterfinal opponent, which will be determined Saturday at Acton-Boxboro. St. John’s went undefeated against in-state teams, with its only loss coming against Barrington (RI).Cameron Trosin (12-4) will play as the team’s No. 1 in singles, after a season in which he proved to be among Massachusetts’ best. In doubles action, the Eagles will use the tandem of Bradley Noyes and Jon Corvi, who went a perfect 16-0 in regular season play. The tandem of Mark Corvi and John Beluch also finished undefeated (15-0), leaving coach Mark Metropolis with a strong sense of confidence.”Both of our top doubles tandems are so strong, and provide us with a definite point almost every match, which I think is a key in our success,” he said. “We have great depth on this team, and as long as we come to play, I think we should be fine.”Also, No. 13 Revere travels to No. 4 Andover Friday (3:30).Division 2 NorthNo. 4 Marblehead leads the local contingent. The team plays host to No. 13 Boston Latin Friday (3:30). Meanwhile, No. 7 Gloucester hosts No. 10 Cambridge Friday (3:30) and No. 9 Danvers visits No. 8 Reading Friday at 4.