SCARBOROUGH — Early in the second set of her team’s Class A volleyball semifinal Wednesday night, Scarborough senior Jillian Harvie served a ball into the net.

Her coach, Jon Roberts, clapped his hands with delight. Not once in the opening set, won by upset-minded Yarmouth, had Scarborough missed a serve.

“I said that’s not being aggressive enough,” Roberts said. “So we went back and started serving a lot harder and putting pressure on their passers. I think that was a big difference in the game.”

Asia Mattress, Caroline Goodwin and Kacey Foerster also made serving errors for Scarborough in that critical second set, but the defending state champions asserted themselves at net and pulled away for a 3-1 victory.

No. 2 Scarborough (16-1) will face No. 1 Greely (16-0) for the state title for the second year in a row, Friday night at Gorham High.

Sixth-seeded Yarmouth (12-5) was coming off a quarterfinal upset of No. 3 Biddeford despite the Clippers playing without senior captain Rachel Chille, who did not receive clearance to play Wednesday night because of the effects of a collision in a match six days earlier.

“We were disappointed about that because certainly we’re a better team when Rachel’s on the floor,” Yarmouth Coach Jim Senecal said. “She’s a terrific player and certainly one of the top outside hitters in the league. We missed her but … we had the same team that beat Biddeford. We thought we had a team that could be successful tonight, especially after that first set.”

Indeed, Alison Clark racked up 13 kills as the Clippers won the first set 25-21 after trailing 12-9. Five of her kills originated from the back row and another two were on dinks.

“After the first set we talked a lot about how we needed to position our blocks,” said Scarborough senior Jordyn Cowan. “We talked about closing the block. There was a gap in the beginning.”

In the second set, Foerster used her jump serve to help score six points. She added four kills to go along with two each for Mattress, a freshman, and Natalie Simonton, a junior, and Cowan also had a kill as Scarborough raced to a 16-6 lead and won 25-17.

The Red Storm took the second and third sets 25-9 and 25-17.

“We have such great hitters,” Scarborough senior libero Emma Budway said. “You can really set anyone and you know they’re going to perform well.”

Harvie, Haley Nelson and Libby Chadbourne each had a strong serving run in the third set for Scarborough, including four service winners. Cowan had five kills and a block, and four teammates registered kills in the third set. Foerster put down four kills in the fourth.

“Their size was a little too much for us,” Senecal said. “When we were the ones being aggressive and we were swinging hard, we were right there with them. But when we were waiting for them to hit, there’s no contest, they’re a much better team in that type of a game.”