GRUNDY CENTER — On to the next challenge.

Grundy Center football carries a 21-game winning streak into Friday’s Class 1A postseason opener at home against Cascade. Kickoff at Spartan Stadium is 7 p.m.

The top-ranked Spartans (8-0) outscored their opposition by an average of 25 points per game this season and are the only remaining undefeated team in 1A, moving up a class after going undefeated for a state title in Class A last fall.

The target’s never been bigger on the Spartans.

“We’re gonna get everyone’s best shot, and we accept that challenge, we want that challenge,” Grundy Center head coach Travis Zajac said. “All of this group’s physical abilities aside, we’ve got hard-nosed kids that have done everything we’ve asked of them getting ready for this second season.”

Grundy Center senior Justin Knaack leads the Spartans’ rushing attack with 87 carries for 492 yards and nine touchdowns. Quarterback Colin Gordon adds three rushing touchdowns on 395 yards rushing to go with 1,127 passing yards and 15 touchdowns to three interceptions. Tiernan Vokes is Gordon’s top target, hauling in 25 passes for 426 yards and eight touchdowns.

“There’s a high bar for us,” Knaack said. “We have to prove ourselves and that keeps us driving throughout the season. … We finished 8-0 but now we can’t lose, so we just have to hold our techniques and play the best we can.”

The Spartan defense often played a critical role in maintaining Grundy Center’s streak of excellence in Class A and that has not changed in the move to 1A.

Guided by award-winning defensive coordinator Chris Conger, Grundy Center once again boasts one of the best defenses in 1A, which has been instrumental in several victories this season.

Most notable among them was a 21-14 victory over Waterloo Columbus on Sept. 21 where two defensive touchdowns kept the Spartans one step ahead for a tough road victory.

“Coach Conger puts together a great plan each week,” said GC senior Tanner Laube. “We make every team work for their yards, every week.”

Iowa commit Trent Cakerice leads the Spartan defense with 10 tackles for loss and five quarterback sacks. Ryder Ross has made 7.5 tackles for loss and Pete Lebo and Vokes add seven and five tackles for loss, respectively. The Spartans also have 13 takeaways this season — nine interceptions and four fumble recoveries.

“If it takes us a little bit to work out things offensively, our defense is going to play well enough to keep us close,” Zajac said. “Our kids just refuse to lie down, refuse to give up and find a way to turn it on.”

This year’s senior class for the Spartans benefit from what’s become a winning tradition in Grundy Center, which includes four consecutive championship game appearances in Class A. Those seniors are all too happy to pay forward what they’ve learned from the seniors before them.

“It’s all about building a relationship with the freshmen,” Knaack said. “Talking to them, having fun with them, just building that bridge between each other, that helps them look up to you more and lets them follow in your footsteps.”

The Cougars (2-6) are led by senior Will Hosch, who has thrown for over 1,000 yards this season and rushed 90 times for 342 yards accounting for a total of 14 touchdowns by land and air. Junior Nathan Schnockemoehl leads the team in receiving and tackles, as well as a team-best four interceptions.

Zajac is familiar with the program from his time spent coaching in Dubuque County between stints at Dubuque Wahlert and the University of Dubuque.

Cascade snuck in as the four-seed in Class 1A District 3 with wins against Dyersville Beckman and Durant in the final two weeks of the season.

“They’re scrappy kids that play really, really hard,” Zajac said. “I know they’re gonna have a lot of pride coming over here. They’ve had some injuries, their numbers are low, but I expect them to put up a really good football game against us.”