Right at the midway point, the alarm for the Jamesville-DeWitt girls basketball team went off.

Trailing Elmont by as much as eight in Friday afternoon state Class A semifinal at Troy’s Hudson Valley Community College, the Red Rams responded with a dominant second half that produced a 67-42 victory over the Spartans.

During the course of the last two periods, J-D outscored Elmont 41-9, a brilliant all-around effort that was reminiscent of many regular-season games where it overwhelmed foes. Only now, the stakes for the Rams were higher – namely, a chance to advance to the state final for the third consecutive year.

J-D had hoped point guard Kasey Vaughan could return and make an appearance off the bench, but her ankle injury was too severe to go.

Where Vaughan’s absence hurt most, at least in the early going, was on the defensive side. Elmont kept converting from long range to match baskets with the Rams during most of the first quarter.

However, the Rams responded to that barrage with one of its own. Two 3-pointers by Meg Hair, and another from Angela Bussone, pushed J-D in front of the Spartans 20-14 by the time they reached the second period.

Elmont didn’t get rattled by this, at least not right away. Zhania Thybulle’s trio of baskets began a sustained run where it outscored the Rams 19-5 to grab an eight-point lead.

Now the Rams responded, netting the last four points of the half to only trail 33-29 at the break, having got nearly half its offense from Jamie Boeheim’s total of 12 points.

Even  with 60 percent shooting, J-D was behind because the Spartans, led by Kem Nwabudu’s 10 first-half points, made 64 percent of its field-goal attempts.

The Rams took notice of this – and smothered Elmont the rest of the way, getting its rotation of guards into the faces of any Elmont player trying to advance the ball or take a shot. That proved quite effective.

Meanwhile, those late-second-quarter baskets provided momentum that carried over into the third quarter, when the Rams extended its run to 11-0 and, with another Hair 3-pointer, broke a 33-33 tie to go back in front, this time for good.

Newly energized, J-D’s defense regained its bite, shutting down Elmont for a long stretch as the run grew to 17-0, energy on one end leading to production on the other. In particular, the Spartans found it impossible to contain Hair, who got 14 points in the third quarter alone.

Yet the Rams weren’t content, even with a 53-39 lead going to the fourth quarter. It kept playing at a high level, limiting Elmont to three points while doubling its ultimate winning margin.

Ultimately, Hair finished with 27 points, and Boeheim gained 19 points, ably splitting front-line production with Julia Kelner, who produced 14 points. Combined, that trio accounted for all but three of J-D’s field goals.

In Saturday night’s state title game at 7 p.m., the Rams face Pittsford Mendon, the Section V champions,who broke out of a tight battle with Somers (Section I) in the fourth quarter to prevail 53-41 in the other state semifinal.