QUINCY -- It's no secret what the Quincy High School boys basketball team plans to do defensively.
How the Blue Devils do it is the mystery opponents have struggled to reveal.
Alton coach Eric Smith had an idea after the Blue Devils' 1-2-2 zone held the Redbirds 25 points below their season scoring average in last Friday's 57-36 victory in the Class 4A Quincy Regional championship game at Blue Devil Gym.
"It's their physicality," Smith said. "We had trouble scoring. Usually, we spend a little more time going to the free-throw line and going to the rim. But they don't let you do that. We told our kids that's the way it was going to be. They are big, physical, strong kids."
Combine that with Quincy's quickness at the guard spots, and it's been a tough combination to crack.
During the eight-game winning streak the sixth-ranked Blue Devils (23-4) carry into Tuesday's Class 4A Pekin Sectional semifinal against second-ranked Belleville West (27-2) at Alton High School, they have allowed just 38.8 points per game. The only team to score more than 41 points in that stretch was Geneva, but the Blue Devils led 53-25 before pulling the starters.
Opponents are shooting just 38.3 percent from the field in that same stretch.
"It all starts with energy which leads to our communication which kickstarts our defense," Quincy senior point guard Aaron Shoot said. "When our defense gets going, our offense gets going."
Both will have to be in sync to challenge the Maroons.
Belleville West hasn't lost since an 81-77 overtime setback against St. Louis Chaminade in the Belleville East Classic championship game Jan. 20. In the 10 victories since, the Maroons have scored 80 or more points three times and reached 100 points once.
Belleville West is averaging 74.6 points per game.
Alton averaged 61 points per game and Collinsville, which Quincy beat in the regional opener, averaged 60 points per game. Neither reached 40. Rock Island, which won a regional title and faces Moline in the other Pekin Sectional semifinal, scored just 37 points against Quincy in their most recent meeting.
That's 17 points below the Rocks' season average.
"I can't say enough good things about the way our guys play defense and the effort they put into," Quincy coach Andy Douglas said. "They love drawing charges. They love creating turnovers. They love causing havoc.
"It's what we've been really good at doing, but we know that won't be easy to do moving forward."
Belleville West hasn't scored less than 62 points in a game this season.
Having a dynamic presence like E.J. Liddell helps. The 6-foot-7 junior forward is averaging 20.9 points, while shooting 57.3 percent from the field and 78.2 percent from the free-throw line. The Blue Devils have made 253 free throws this season, while Liddell has attempted 243 himself.
Liddell isn't the Maroons' only option. Malachi Smith, a 6-foot-3 senior guard, is averaging 15.9 points, while junior guard Lawrence Brazil III is averaging 10.9 points and has made a team-leading 44 3-pointers.
"Our defense sparks our energy," Quincy junior guard Jaeden Smith said. "We know we have to be good defensively."
The Blue Devils have to approach this game the way they approached the Alton matchup.
They have to be aggressive.
"Coach said before the game, ‘They haven't seen a defense like this all year. Go at them hard,'" Quincy senior forward Ben Amos said. "And we did. We knew it was going to be something new for them. We knew that was going to disrupt them."