"We have to use our speed to our advantage. That's all you can do," said Castillo. "We don't have a lot of big guys who can throw people around. In my case, I have to try and get through as quickly as I can. I really can't manhandle anyone."

The program might not show a lot of big bodies on the Purple Raiders' defense.

What the program also doesn't show, defensive coordinator Don Anderson will tell you, is heart sizes.

"The past two games, we've played our best defense. We made some changes in practice, and the kids have embraced it," said Anderson. "They've played with a lot of heart and emotion. In the playoffs, that's what you have to do on defense.

"You've got to play with emotion -- and with emotion for four quarters."

BHS' defense will try to continue its inspired play tonight. The Raiders (12-0) face St. Rita (11-1) in a 7 o'clock Class 6A semifinal playoff game at Chicago.

In three playoff victories, BHS has allowed 26 points. They have come a long way since the beginning of the season.

Linebacker Justin Harrison, end Dan Pettie and Castillo were the only returning full-time starters from last season. The hard-hitting Harrison was moved from strong safety, where the University of Illinois recruit figures to play the next four seasons for the Illini.

Normal Community moved the ball up and down the field in the season's second game against BHS. The Raiders finally stopped the Ironmen in the fourth quarter and the Raiders were able to pull out a 24-20 victory.

During last week's rematch in the quarterfinals, BHS played like a different defense. The Raiders held NCHS to 226 yards en route to an 18-6 victory.

"Week two was full of a lot of mistakes. You could tell we were a young defense," said senior cornerback Brandon Hughes. "A lot of people were just learning their positions. There were a lot of mistakes made. Against Normal (Community) last week, you could tell we're more comfortable playing our positions."

Anderson sensed a 180-degree turnaround in a 10-week span.

"We were not sure if we could stop them (the first game). This past week they again gained some yards, but we had confidence we were going to stop them," said Anderson. "We knew they would get a couple first downs, but we could make some adjustments and pick it up and we were going to stop them."

It took Harrison a while to reconnect with fellow linebacker Dane Ramirez.

"I lined up with Dane our freshmen and sophomore years," said Harrison. "We weren't communicating well at the beginning of the season. But now it's like we've been going at it four straight years again."

Anderson said he needed Harrison at linebacker to cover the whole field instead of just one side at strong safety. Harrison, who made 21 tackles during a 19-14 second-round victory against Rock Island, accepted the assignment.

"It was a big move. I knew it was going to put me inside against a lot bigger people," he said. "I'm more of a free range, put my head on a swivel and make a tackle. It was a big switch from last year, where I was outside and two yards off the ball. I could run wherever I wanted to and make more tackles in the open field. But it was the best move for the team."

Harrison and Ramirez are BHS' leading tacklers with 95 and 85, respectively. Castillo, who has three sacks and three fumble recoveries, is next with 73.

Pettie, who has blocked a punt in each of the past two games that Harrison has returned for touchdowns, paces the team with five sacks. Junior cornerback Donald Brown has seven interceptions.

Juniors Matt Logsdon, the biggest-bodied defender at 258 pounds, and Erik Miller are the tackles, with senior Ryan Esch at the other end. Junior Rod Arrington lines up at strong safety, while free safety has been held by senior John Hamrin and sophomores Brent Holtz and Dustin Kelly.

At the beginning of the season, Castillo wasn't sure the defense could help take BHS to its third straight semifinal appearance.

"It was pretty shaky. We had a lot of underclassmen and not a lot of returning starters," said Castillo. "We graduated a lot of seniors and important parts of the defense. I was worried. I didn't think the underclassmen would step up to the challenge."

Castillo is glad he was wrong.

Contact Jim Benson at jbenson@pantagraph.com