With the chance to avenge an early exit from last year's playoffs in an upset loss to Buffalo Grove, Glenbrook South seized the opportunity.
The Titans (20-4-4) struck back with two first-half goals after the Bison had stunned the favored veteran Central Suburban League club with a 13th-minute goal from Colleen Zickert.
Fifth-seeded Glenbrook South then held off the No. 2 seed the rest of the way to earn a 2-1 victory Friday night in Class 3A sectional championship play at Palatine. The Titans will meet New Trier in Tuesday's Niles North supersectional.
With the Titans cruising along on a 13-game winning streak and looking unstoppable in their sectional opener against the host Pirates, the Bison opened the match with more energy and pace than their opponents and immediately put Glenbrook South under pressure when Zickert finished past keeper Kelsey Byers a wonderful serve delivered by Kelli Zickert.
"It's been a long time since we've been chasing the lead, but I had a lot of faith in our team," said senior Keeley Nolan, who wears the captain's armband for coach Seong Ha.
"We came in with a little chip on our shoulders because of what happened here last year, but I've got to say, Buffalo Grove has a lot of talent -- young, skilled talent -- and they put us on our heels almost right away," said Ha. "But I knew, just as we saw when we went down 2-0 to Maine South, that if we got back to playing our game, we could get back in this one and get the result that we wanted."
The Bison (15-6-1), who made sure to play through freshman midfielder Jessica Kovach, enjoyed the run of play for most of the first quarter hour.
"We were aware of their speed on top, in particular No. 20 (April Cronin), but we felt that we had a good game plan in place to counter what they do so well," said BG coach Pat Dudle. "But it was their set piece and dead ball opportunities that we struggled with."
At the end of a nice three-minute sequence when the Titans would finally find their pace, Nolan's free kick from just inside the midline slipped through the 6-yard box, where an opportunistic Colleen McDonagh found a way to slot under keeper Katie Okamoto through a mass of players for the equalizer.
Cronin gave the Titans the lead for good when she finished her 26th goal of the season following an inwarding swinging corner from Carolyn Nash. Okamoto punched it clear of the area but right to the foot of Cronin, who thumped in the go-ahead goal with a superb one-timer.
"It was tough giving up that first goal, but another one, and off of a corner, is not a very good thing to do in a big game like this," said Dudle.
The Bison hoped to get even after the break by limiting touches for Cronin and her running mate Eleni Haramaras. But Glenbrook South defended well in front of second-half keeper Emma Sailer.
The best chance fell to BG senior Carolynn Wieland, who took a lovely ball from Kovach, and unloaded a bending ball which was curving away from a horizontal Sailer, who still somehow pulled the Wieland attempt out of the air.
The Sailer save in the 66th minute was a prelude to a frantic conclusion, which saw the Bison throwing numbers forward with each counter-attack, but an air-tight backline led by Nolan was enough to keep the Bison off the scoreboard.
"It's kind of hard to believe we're in the supers after opening the season 3-3-4," said a relieved Ha. "But all I know is that for a couple of years, it was us and Hersey in some real epic battles, and now it looks like another great team is coming out of the MSL to keep an eye on, they are going to be a real good team for several years."
Dudle took some time to thank his five seniors before making the long walk to the team bus.
"What a great year we just finished," said Dudle. "We had a terrific group of seniors who provided so much leadership, and it's tough to see them done for good. But on the other side of things, I believe we're slowly building something here that has a chance to do some wonderful things."