Longtime Marblehead girls soccer coach Sam Yawson announced that he would be stepping down from the post that he has held for 15 years because of a new job.”I’m very disappointed,” Yawson said. “I just wasn’t going to be able to do it, though, without shortchanging the kids. I didn’t want to do that. So I knew it was time.”In the 15 years Yawson was coach, the Magicians only missed the tournament one time. His teams won Northeastern Conference crowns in 2002 and 2004. The 2002 team was the Eastern Massachusetts champion, but lost in the state final.”It has been a great experience for me,” said Yawson. “I’ve met a lot of good people and families. I want to thank Marblehead for giving me a shot. I just hope I didn’t disappoint anyone.”Athletic director Michael Plansky will start the search for his replacement in the coming days.”He was great for our school,” Plansky said. “He brought a lot of stability to our soccer program. I’m really sorry to let him go.”