North Branford — Everything that was right two days ago, crisp defense, timely hitting, confidence, unraveled for the Waterford High School softball team Friday afternoon in the quarterfinals of the Class M state tournament.

A lot of it had to do with one person: North Branford senior left-hander Sydney Senerchia.

“That girl dominated us. She had great command,” Waterford coach Andy Walker said.

Senerchia one-hit Waterford, striking out 12, as No. 2 North Branford, still unbeaten at 26-0, advanced to the semifinals with an 8-0 victory over the 26th-seeded Lancers. Waterford upended No. 10 Montville 2-0 in the second round of the tournament Wednesday behind a four-hitter from Rachel Miller.

Against Senerchia, who will pitch next season at Division I Saint Peter's (N.J.), the Lancers' only hit was a bunt single by Miller in the fourth.

They managed only one other base runner on a walk by Gina McKittrick in the fifth, as Senerchia struck out the side in the second and the third.

“It's hard to pinpoint. I think we had great energy coming into this game. We were confident,” Walker said, before adding with a laugh. “At least I was. That was a great win, a great team win against Montville. I thought we could come in here, put them to sleep quick, score a few runs, get out of here and go play Griswold (in the semifinals).

“(North Branford was) good. I told the girls afterward, sometimes you've got to tip your cap to someone. Whether it was 8-0 or 1-0, we just couldn't square up on a ball.”

North Branford scored an unearned run in the first inning when Kayla Despres singled, Olivia Hemstock reached on an error, putting runners on second and third, and Jada Miconi grounded back to the pitcher to score Despres.

It remained 1-0 through three, as Miller got some defensive help in the second on a nice pickup at first by Madison Nott and a stab of a line drive by third baseman Taylor Lee.

North Branford struck for five with two outs in the fourth, however. With two on, Senerchia doubled off the right field fence to score both runners and make it 3-0. Miller then walked Amy Raucci and Walker went to the bullpen for senior Ashley Goldstein for a change of pace, he said. Goldstein struggled through her first couple of hitters, giving up a two-run single to Angelina Ramada, before getting out of the inning with a fly ball to center.

The two pitchers combined to walk three and throw four wild pitches in the inning.

North Branford, ranked third in the GameTimeCT/New Haven Register state poll, added two in the sixth on an RBI double by Raucci and a sacrifice fly by Ramada.

“I knew that they had a few good hitters. I had to work on hitting my spots,” said Senerchia, a right fielder her first two seasons with the Thunderbirds who now has 284 strikeouts this season to go with a 23-0 record. “Just working on hitting our corners, inside and outside.

“It's been a really exciting season. I'm proud of the girls and all the hard work we've done. I'm nervous (about reaching the semifinals), but excited. I think I'm definitely more confident (than in previous seasons), now that we're able to have a good team. I'm definitely more confident and I have a few more pitches.”

Waterford finished 15-11 with a share of the Eastern Connecticut Conference Division II title.

v.fulkerson@theday.com