DETROIT — Christmas bowl games often turn into scoring bonanzas, where the first team to 40 points is the winner.

The GameAbove Sports Bowl might be the exception to that rule — 20 points could be more than enough.

The game Friday pits Northwestern and Central Michigan, two Great Lakes schools that combine strong defenses with low-scoring offenses.

The Wildcats (6-6) are 34th in the country defensively, allowing 20.9 points per game, but 103rd on offense at 22.5. The Chippewas (7-5) are built along the same lines, ranking 50th on defense (22.7 points per game) and 93rd offensively (23.8).

“When we turned on the tape, it was like looking in the mirror,” Northwestern coach David Braun said. “Central Michigan is a team that is committed to running the ball and playing great defense. It is a team with great fundamentals and great technique, and a great deal of physicality. Those are the same things we teach at Northwestern.”

Central Michigan coach Matt Drinkall had the same experience when he began preparations for the game.

“I chuckled when Coach Braun said that about looking in the mirror, because we were like, ‘I already know what this film is going to look like before I turn it on,’” he said. “Then you turn it on and it reaffirms everything you want to see from a good football team.”

Tiernan at home

The Wildcats might focus on the defensive side of the ball, but their biggest star will be playing offense in front of home fans. Offensive tackle Caleb Tiernan was named to the All-Big Ten second team and is considered one of the best linemen in the country. Ford Field is located less than 20 miles from Detroit Country Day, where Tiernan played in high school.

His college career will end in the same stadium as his high school career: He finished his run at Country Day with a state championship won at Ford Field.

“In my junior year, we lost there, so I wasn’t much of a fan of that place,” he said. “But I won in my senior year and the Lions have started to win, so my attitude has changed. I’m extremely excited to play there this year.”

Platoon-style quarterbacking

Central Michigan historically has built around running quarterbacks, but it helps if they can throw a little. This season, the Chippewas are getting that production by using two players at the position.

Joe Labas, who started his career at Iowa, is the passer. He has thrown for 1,676 yards and 12 touchdowns, completing 68.9% of his passes with only six interceptions. He is not a runner, though, having gained minus-4 yards on the ground with no touchdowns.

That’s where Angel Flores comes in. He is second on the team with 519 yards rushing and leads the Chippewas with eight touchdowns. He is not a terrible passer, averaging 7.2 yards per attempt, but he averages fewer than four passes per game.

Fitzgerald leads the defense

Northwestern cornerback Robert Fitzgerald intercepted only one pass but led the Big Ten with 68 solo tackles and six tackles for loss. He can’t be accused of padding his stats against the easiest teams on the Wildcats’ schedule: He had 10 solo tackles and an interception against Michigan, 13 total tackles against Tulane, 10 against Oregon and eight at Southern California.

Heldman key for Central

If the Chippewas have a chance at the Boxing Day upset (the Wildcats are favored by 10 1/2 points, according to BetMGM Sportsbook), they will need a big day from defensive lineman Michael Heldman. The redshirt senior finished the season with 10 1/2 sacks and 16 1/2 tackles for loss, including five sacks and 7 1/2 tackles for loss in the final three games of the season.

Central Michigan won the first two of those games, beating Buffalo and Kent State to get to 7-4 before losing the finale to Toledo.