A 5-foot-9 tailback who wears No.25 and attends a high school that borders 42nd Street NE could have a profound effect on the Class 4A playoffs Friday night.

The question is: Which one?

Miles Moa has rushed for 1,436 yards for the Kennedy Cougars this season, the sixth-most in Class 4A, and galloped for a school-record 300 yards a few weeks ago.

Brendan Miller has scooted for 1,323 yards for the Xavier Saints, the eighth-most in Class 4A, and set a school record with 268 yards this year.

They'll clash at 7 p.m. Friday at Saints Field in the 4A quarterfinals.

Both clubs have strong defensive units, but Xavier's defense has been exceptional this year. The Saints have allowed only 130.7 yards of total offense and 5.5 points per game - permitting just 69 yards rushing and 61.7 yards passing per contest.

The Saints were even better than that when they blanked Kennedy, 24-0, on Sept. 27, holding the Cougars to 57 yards on the ground and a mere 19 through the air.

If that happens again, Kennedy will pack its bags and crawl home on 42nd Street.

"I like to think we're a better football team than we were in Week 5," said Kennedy Coach Tim Lewis. "The kids are excited, the coaches are excited, the school is excited, so we're looking forward to Friday night."

Kennedy has improved drastically since firing blanks against the Saints for the third straight year. The Cougars have averaged a healthy 36 points per game since being shut out by Xavier, compared to just 15 points per game in the first five contests.

Moa, who rushed for just 41 yards against Xavier, has been on a tear since then with 183 yards against Jefferson, 139 against Waterloo East, 151 against Dubuque Hempstead, 300 against Iowa City High, 123 against Prairie and 187 against Davenport Assumption.

By no coincidence, the Cougars have compiled a 5-1 record in those games and swatted Assumption in the second round of the playoffs Monday night.

Xavier Coach Duane Schulte is well-aware of Kennedy's vast improvement since the first time he faced them.

"Their kids are just doing their job, it seems like," he said. "They're doing their stuff. Maybe they're executing it better, I don't know. They're better. Let's put it that way."

Both clubs have been impressive in the playoffs. The Saints (10-1) have blanked Clinton, 45-0, and Iowa City High, 34-0. The Cougars (8-3) topped Prairie, 42-14, and Davenport Assumption, 35-12, with strong efforts in the second half of both games.

The Saints have rolled 79-0 in the playoffs, but Schulte described his club's performances so far as "up and down."

"We've had our good moments and our bad," he said. "Both games ended the way we wanted to and we got a little momentum going. But we're not perfect. Trust me. We're still just trying to do the same old stuff. Do our job and execute."

Kennedy is seeded No.7 in the Eastern half of the playoffs. The Cougars erased Assumption, the No.2 seed, on Monday. Now they'll be tangling with the No.3 seed - a team that was ranked No.1 in all the polls until it got ambushed by Washington, 26-10, on Oct. 4.

The Cougars know the entire world sees them as underdogs.

"We can't start slow," said Seth Gilmore, a two-way starter at offensive tackle and nose guard. "When we played them in Week 5, I don't think we even got the ball across midfield until the second half.

"Offensively we have to come out strong," said Gilmore, who has trimmed from 320 pounds to 282 since the summer. "We have to set the tone first. We have to hit them in the mouth. They can't hit us."

It promises to be a physical game, with both clubs featuring big, strong, fast players who do not shy away from contact.

Kennedy has not scored a single point against Xavier in the last three meetings. That's 12 quarters of football without a single marker.

"They run to the ball extremely well," said Lewis. "They have good speed, they're big up front and they play really, really aggressive defense. I like to say that we do the same type of stuff. That's what we preach, anyway, but they really do it."

The Saints have been scraped a few times this season on defense. Washington quarterback Reid Snitker completed 12 of 16 passes for 191 yards when the Warriors stunned them in early October. Linn-Mar tailback Perrion Scott ran for 200 yards against them and Cedar Falls tailback Eli Berregaard netted 161 yards, but otherwise they've been near impregnable.

Xavier has collected seven shutouts in 11 games.

"I would like to think that our kids aren't scared of them," said Lewis. "Even though we haven't beaten them for awhile, the kids still are not intimidated by them."

Xavier owns an 11-5 lead in the series. The Saints defeated the Cougars during the regular season in 2010, but Kennedy sprung a major 11-7 surprise against the Saints in the playoffs that year.

The Cougars are appearing in the playoffs for the ninth straight year, but have never won a state title. The Saints are appearing in the playoffs for the seventh straight time, with a state title in 2006 and a runnerup finish last year.

Both teams rely on their tailbacks, but both quarterbacks can make plays with their arms and feet. Quinton Scholer has hit 68 percent of his passes for 949 yards and 14 touchdowns for the Saints. Derek Jacobus has completed 50 percent of his throws for 653 yards and seven TDs and is an important part of Kennedy's running attack.

Friday's winner will face Pleasant Valley (11-0) or Bettendorf (9-2) in the semifinals next Friday at the UNI-Dome in Cedar Falls.