CUMBERLAND — Yarmouth High pitcher Mari Cooper has played on the St. Joseph’s College softball diamond before, but Tuesday she’ll play the biggest game of her career there.

The fourth-ranked Clippers took early control and upset top-ranked Greely 7-0 in the Western Class B semifinals Saturday.

The win lifted Yarmouth (15-3) into a regional final for the first time since 1996, when it still played in Class C. Yarmouth will play seventh-ranked Fryeburg Academy at St. Joseph’s.

Greely (14-4) had beaten Yarmouth 12-2 on May 6.

“I can’t even explain (how it feels),” said Cooper. “I’ve never had this happy feeling in my life. I can’t even explain how happy I am.”

Yarmouth scored a run in the first inning on a bases-loaded walk, then two in the second on a bases-loaded walk and a throwing error. Greely’s pitchers combined to walk seven batters in the first two innings.

“It really set the tone,” said Greely Coach Rob Hale of Yarmouth’s first inning. “Although they only scored one (in the first), it put us on our heels right away.”

And the Rangers never recovered.

Cooper was a big reason, allowing two hits with two walks and six strikeouts, and Greely never had a runner reach second. Cooper got the final three outs on just four pitches, with second baseman Sydney St. Pierre ending the game with a nice catch on a line drive.

“Mari threw an amazing game,” said Yarmouth Coach Amy Ashley. “I mean, they’re a tough out. There’s no holes in (the batting order).”

Cooper also was backed by errorless defense for the second consecutive playoff game.

“That’s been huge,” said Cooper. “We’ve always kind of had the offense there but the defense has really stepped up.”

Greely freshman Kelsey Currier, who came in to pitch with two outs in the first, settled down – at one point she got five outs on five consecutive pitches – but the Clippers kept the pressure on throughout.

They scored twice in the fifth, loading the bases with one out on singles by Cooper, Cat Thompson and Eleanor O’Gorman. Michelle Robichaud followed with a two-run double to make it 5-0.

Cooper added a two-run single in the seventh to complete the scoring.

While the Clippers are still a young team, Ashley said, “I knew we had the potential. We still have more potential yet to be reached.”