Seeded No. 1 at Wheaton North's Bill Neibch Falcon Classic, Hersey is still on a path toward its fifth tournament championship.
Glenbard South made the path as rocky as it could before falling 58-53 in Thursday's last quarterfinal.
"We knew it was going to be a tough game going in and we handled it really well and worked well together as a team and came out with what we wanted," Hersey senior Morgan Harris said. "We did a good job breaking their press and hit some free throws in the end."
"We love this tournament," added Hersey coach Mary Fendley. "It's always such great competition. But not every year do we have such great competition in a second-round game. This certainly did."
Hersey (12-1) took a 28-18 lead with 2:14 to play in the second quarter when freshman Claire Gritt hit a 3-pointer. But Glenbard South fought back in the final two minutes, cutting the lead to 31-27 at halftime.
"We expected that," Fendley said. "We had seen them play on Monday, and just looking at the teams that they've played close games with, win or lose I knew they were good. And then when I saw them Monday it confirmed that they were good. We expected a really tough game tonight, and we got all of that."
"I knew if we kept it close at halftime, we had a chance," Glenbard South coach Julie Fonda added.
The Raiders got help off the bench from Megan Smith and Alex LaPonte, who combined for 12 of those 27 first-half points.
"Megan's a gamer," Fonda said. "If you leave her breathing room she's going to take the 3, if you are up in her shirt she's going to drive to the basket, so that doesn't surprise me. And Alex is so feisty on defense she gets some of those defensive points on steals and layups."
Hersey never got the lead back to double digits again, although the Huskies did come close. Each time it looked like they would pull away from the Raiders, the Raiders (9-5) fought back.
"They executed, they played hard, and it's in our DNA, I think," Fonda said of her Raiders. "They definitely executed our game plan. I'm proud of them. I definitely think it was a winnable game for us. In this tournament I think 1 through 8 is pretty evenly matched, if you look at the teams that are here. So I knew it was going to be a good game. Hersey's a good team, don't get me wrong by any means, but it was anybody's game there for a while."
But as close as Glenbard South came, it never could retake the lead in the second half.
"We knew a good team isn't going to collapse if you get up 8 or 10, so we told the kids to expect that," Fendley said. "And when they got it back to within 4 again, or even to within 2, we felt comfortable. We just kept moving our feet on defense and cutting off the baseline. It's a good win for us and it's exciting to get back to the Final Four of this tournament."
Gritt scored a game-high 16 points, Annie Korff added 15 for Hersey and Harris had 12.
Tomei Ball scored 12 despite fouling out for the Raiders, and Sydney Bauman added 11.
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