As a freshman on Crystal Lake South‘s varsity two years ago, Nick Stowasser often played mop-up minutes in blowouts, even during the postseason.

The Gators starters and another freshman named Carson Trivellini, who was the team’s sixth man, were that good.

Wednesday night, Stowasser was one of those seniors who played so well in helping his team to victory that the guys who are now in his old basketball shoes got mop-up minutes.

Stowaser had a double-double at halftime and finished with 14 points and 12 rebounds as South beat Crystal Lake Central 69-32 in a Class 3A Crystal Lake South Regional semifinal.

Stowasser and Trivellini now have been a part of eight postseason wins, including a sectional title two years ago.

“Coming into this game, we knew what we had to do,” Stowasser said after South beat Central by double digits for the third time in as many games this season. “Rebounding was my big focus today, just trying to keep people off the glass and get rebounds and putbacks. That’s a huge part of the game for us. I think that got us some momentum in the early part of the game.”

Trivellini scored a game-high 17 points for No. 3 South (25-7), which will play No. 2 Cary-Grove (28-4) at 6 p.m. Friday for the regional title. C-G, which beat Marmion 78-55 in Wednesday’s first semifinal, beat South 59-52 and 61-53 during the regular season.

“It’s going to be packed,” Trivellini said. “It’s going to be fun.”

South led No. 6 Central (18-14) 6-0 only 54 seconds into the game thanks to a putback by Noah Cook (six points, five rebounds), a layup in transition by Cook after a steal by Trivellini and a steal and two-handed dunk by Stowasser.

Central coach Brian Seaver burned a timeout after the Stowasser slam, but the Tigers never recovered. South was up 17-9 after one quarter, 38-17 at halftime and 55-24 after three.

The fourth quarter was played with a running clock, but South kept scoring, getting five points from sophomore call-up Ian Christopher (3-pointer), four from Wes Bogda, two apiece from Michael Santos and Vince Santarelli and one from Rylan Robinson.

“It was nice to get those guys in there,” said Stowasser, who had two dunks and a 3-pointer in his three quarters of work. “It’s truly fun, especially since they played really well.”

Starters David McFadden (seven points, six rebounds, four steals) and Ryan Morgan (five points) also contributed to the win, while John Morgan had six points on two 3-pointers coming off the bench.

“They’re so lengthy, and they all work as a unit,” Danny Spychala, who led Central with nine points, six rebounds and three blocks, said of the Gators. “They’ve been practicing together forever and building chemistry. They’re just a good group of guys who play hard all the time, and they’re succeeding right now.”

Aidan Watson had eight points for Central, which finished with four straight losses. It marked the Tigers’ longest losing streak, but their 12-win improvement over each of the past two seasons was significant.

“Definitely a step in the right direction,” said Spychala, who will return for his third season as a varsity starter. “We have more of a brotherhood. It’s really encouraging to finally get some wins this season.”

Fox Valley Conference champion Cary-Grove spotted Marmion (19-13) a free throw to start the game, then put together a 12-0 run and never looked back. Dylan Dumele drained one of his three first half 3-pointers, and six Trojans scored in the opening quarter.

Brothers Adam, Brady and Evan Bauer combined for 19 points in helping the Trojans take a 38-19 lead into halftime.

Marmion got a first quarter spark from David Malley, who came off the bench to hit two 3s and knock down three free throws after getting fouled on a shot from outside the arc.

Adam Bauer finished with 17 points and 15 rebounds, while his younger brother Evan had 17 points and four rebounds. Dumele added 16 points, Brady Bauer had nine and Brady Elbert grabbed eight rebounds. Adam Bauer also had three steals and three blocks. He dunked after one of his steals.

“This sub-sectional is insane,” C-G coach Adam McCloud said. “It’s a lot of really good teams. Marmion is a really good team. They do some things really well. Our guys had a great week of prep. We knew that if we could take advantage of our size that we’d be in good shape. [Marmion] didn’t go away, but credit to our guys, every time they made a run, we made a run right back.”

Evan Bauer’s point total was a season high for the varsity rookie. The 6-foot-4 sophomore made all six of his shots from the floor and all five of his free throws.

“He’s capable of that,” McCloud said. “He’s going to be a monster the next two years. He’s going to get more minutes, more opportunities. We’re senior-led, but to have a guy who can come off the bench and give you 17 [points], it’s hard to duplicate.”

Marmion was led by Benjamin Piekarz’s 12 points. Ali Tharwani and Malley each had 11.