Danielle Rauch made some history. Then she did something far more important.

On the afternoon where she became her school’s all-time leading scorer, Rauch’s free throw with three seconds left helped the top-seeded Bishop Ludden girls basketball team edge no. 4 seed South Jefferson 51-50 in Sunday’s Section III Class B semifinal at SRC Arena.

For four quarters, the Spartans forced Ludden to exert a full effort, and answered every time the Gaelic Knights tried to put them away. It did so again when Natalie Burdick hit a 3-pointer with 20 seconds left to tie the game, 50-50.

Though the Spartans knew that Rauch would get the ball, the junior still drove to the basket and forced Savannah Fish to foul her. Adding to the pressure, Rauch missed the first free throw, but swished the second,

South Jefferson still had a chance to win, but tight Ludden pressure forced Mackenzie Riordan into a shot that fell well short of the rim at the horn.

Rauch, coming off a tremendous effort in the Gaelic Knights’ quarterfinal win over Utica-Notre Dame (35 points, 11 steals, eight rebounds, eight assists) knew she would serve as an opponent’s primary focus, and  was subject to intense pressure from the outset, sometimes seeing double and triple teams.

The game was played  on the Spartans’ terms, with the Gaelic Knights only leading 10-8 at the end of it despite holding South Jefferson without a point for the game’s first four-plus minutes.

Rauch did not hit on a field goal until the midway point of the second period. Laura Patulski had 10 first-half points, but otherwise Ludden struggled on every possession, and the Spartans produced enough to close the gap to one, 24-23, by the time they reached the break.

Sensing the danger, the Gaelic Knights picked up its defensive intensity in the third quarter, not letting the Spartans move in front. Meanwhile, Rauch scored eight points, including the free throw that sent her past Carm Petrera’s mark of 1,434 career points.

Even with that, though, South Jefferson used a 7-0 run to move in front for the first time, 37-36, early in the fourth quarter, only to have Ludden counter with an 8-0 run of its own.

Yet that didn’t kill the Spartans, either, as it used a 10-2 spurt capped by Alyssa Stevenson’s basket to grab a 47-46 lead. Maintaining its poise, the Gaelic Knights used Laura Patulski’s jumper with 1:33 left to go back in front, and Rauch’s pair of foul shots made it 50-47.

A bigger free throw would follow, Rauch’s 23rd point of the game, with 17 of them coming in the second half. Patulski finished with 15 points. Stevenson and Mara Hathaway led the Spartans with 14 points apiece, but Ludden held South Jefferson’s main threat, Jenna Zimmerman, to eight points.

Hours later, in the other Class B sectional semifinal at nearby Allyn Hall, the defending champions, Westhill, could not join its neighbors in next weekend’s sectional final, beaten 47-44 by Bishop Grimes in another game decided at the free-throw line.

The Warriors led, 44-42, with slightly more than a minute to play, but then committed a string of fouls, all of them against Grimes sophomore forward Abby Wilkinson.

With remarkable poise, Wilkinson made five of those six free throws, and Westhill came up empty on offense in each of its possessions during the final minute.

Westhill held Grimes to nine points in the opening quarter and built its lead to 19-11 early in the second period. Even after the Cobras’ Azariah Wade made back-to-back baskets, the Warriors built the margin back to 23-16 by halftime.

Mackeznie Martin, with 15 points, nearly matched Grimes by herself in those first two periods, only to see Wade net seven points to ignite a 10-0 run at the start of the third quarter that Molly McInerney (who didn’t play in the Cobras’ loss to Westhill in early January) capped with a 3-pointer, giving her side a 29-28 lead.

Even though Westhill went back in front, 34-30, by the end of the period, Wade again tied it with back-to-back baskets early in the fourth quarter, and from there neither side would gain any kind of separation.

Martin’s basket with just under two minutes left had Westhill up 44-40. It would not score again, though, as Wade, who had 15 of her 22 points in the second half, netted one more basket, setting up Wilkinson’s late heroics as Grimes avenged not just its regular-season loss to the Warriors, but three straight sectional defeats.

So it’s Grimes taking on Ludden this Sunday at Allyn Hall at 3:45 for the sectional title. The Gaelic Knights won 51-45 on the Cobras’ home floor Feb. 9, but the second encounter has a lot more on the line.

E.Jay Zarett contributed to this report.