YORK — For more than 29 minutes, the Kennebunk field hockey team battled undefeated and top-ranked York to a stalemate in Tuesday’s Western Class B semifinal.

Unfortunately for the Rams, a half lasts 30 minutes, and the entire atmosphere of the game changed in the final moments of the first half.

With 37.5 seconds remaining before halftime, York sophomore standout Lily Posternak took in the insertion pass on a penalty corner, surveyed the situation and unleashed a rocket of a shot from the top of the circle that took little time in finding the bottom left corner of the Rams’ net to give the Wildcats a 1-0 lead.

With the momentum-building goal and the lead on its side, York came out of the gates in the second half and dominated, getting another goal from Posternak midway through the half and a late insurance goal via Devon Datsis to top the fourth-seeded Rams 3-0 at York High School.

Despite the Wildcats’ later control of most of the final 30 minutes, both teams felt that turning point came on Posternak’s first goal, which rendered much of the Rams’ strong defensive work in the opening half moot.

“That was huge and gave us a lot of momentum going into the second half,” Posternak said. “Opportunities don’t come around as often in the playoffs and we took that one. It was only 1-0, but it calmed the nerves.”

“It definitely makes you think and makes you adjust what you’re going to have to do in the next 30 minutes,” Kennebunk coach Kayla Billings said. “For us that just didn’t happen. Unfortunately today was a huge challenge for us and we ran into a very good team.”

York (16-0) will look to reach its ninth state championship in the last 11 years when it faces third-seeded Spruce Mountain ”“ which knocked off No. 2 Leavitt in the day’s other semifinal ”“ in the regional final on Thursday. Kennebunk, whose seven-game win streak was stopped with the defeat, ends its best season in years at 10-6.

York, which has lost seven of those eight previous state games, entered having outscored opponents by a 66-2 margin its first 15 games, including a 2-0 win over the Rams on Sept. 17. But the Wildcats struggled in their playoff opener on Saturday against eighth-seeded Fryeburg in a game that was 0-0 after 50 minutes before two late York goals sealed it.

The Rams looked on their way to lingering just as long Tuesday with a chance to steal things late before Posternak’s strike.

“You can breath a little easier when you know you’ve got one on the board,” York coach Barb Marois said. “Not that 1-0 is very comfortable in these games, but against Fryeburg we were nerved up by the fact we hadn’t scored and had our opportunities. We just kept plugging today and one fell.”

Posternak, a sophomore, is already known as one of the most dangerous players in the state ”“ as well as a member of the U.S. under-17 national team ”“ and showed why Tuesday, routinely dribbling her way through several Kennebunk players when in possession and many times getting the Wildcats out of danger with solid plays in the defensive end.

But after the Wildcats had failed to beat Kennebunk goalie Liv Kudas (nine saves) despite seven penalty corners and four shots on goal, it was a head’s-up play by Posternak that at last got York on the scoreboard in the final minute.

Receiving the insertion pass from Kayla Kelly on a play that was designed to work the ball to the far post, Posternak instead decided on a more direct approach, firing a low and hard shot that left Kudas with no chance at a save.

“We had a play in mind where I was supposed to pass it to Devin, but I had to read the defense and the situation,” Posternak said. “I knew I had to take a shot.”

“We had called a certain corner and she noticed that something else was going to work, so she just kept it,” Marois said. “She sees the field really well and took charge of the situation.”

Posternak made it 2-0 off another corner with 14:11 to play, this time setting up in front of the goal and receiving a pass from Kara Kelly, with some quick stick work setting up a back-handed shot that got past Kudas.

Held without a corner or a shot on goal for the first 50 minutes, the Rams got both with 10 minutes left when an Allie Gregoire shot was soon followed by a corner that led to nothing.

The Rams’ best chance came three minutes later, when a bouncing shot by Samantha Auriemma was nicely saved by York goalie Olivia Gollini. Datsis then made it 3-0 with 3:24 left ”“ again on a corner, and knocking in a rebound after a shot by Kayla Kelly ”“ to end the scoring.

York held a 13-2 advantage in shots on goal overall, and a 17-2 advantage on corners.

“We wanted to have a bit of a more offensive push,” Billings said. “But we just weren’t able to get it done today.”

—Staff Writer Cameron Dunbar can be contacted at 282-1535, ext. 323 or [email protected].