Only one-quarter of a team's schedule consists of interconference games, but it seems those NFC vs. AFC matchups can produce half or more of the head-scratching results.

Just look at the Packers. For all of Mike McCarthy's success as a head coach, he's just 14-12 in the regular season during his career against AFC teams heading into this Sunday's meeting against the Jacksonville Jaguars at Lambeau Field.

That .538 winning percentage pales in comparison to McCarthy's .688 regular-season mark (53-24) against NFC opponents. So what gives?

For the Packers, the lack of familiarity might work against them more often than not. McCarthy is a stellar 28-9 (.757) against NFC North foes, the teams he knows best. Due to the NFL's rotating schedule, an AFC opponent is seen only once every four years.

"Uncommon opponents really from a preparation standpoint are always a little more challenging," McCarthy said. "There's always a little more of the unknown when you play these types of games."

That cuts both ways, of course, but it helps to explain some results in recent years that, in retrospect, seem a little baffling.

In 2008, a Packers team that would end up 6-10 beat an Indianapolis Colts team that finished 12-4.

In 2010, the eventual Super Bowl champion Packers lost at home to what became a 7-9 Miami Dolphins team and won on the road, via shutout, against a New York Jets team that would reach the AFC title game.

In 2011, the Packers' lone loss in a 15-1 regular season came at Kansas City, and the Chiefs finished 7-9.

Even this year, the Packers lost to a Colts team with a rookie quarterback and then took a sub-.500 record into previously unbeaten Houston and steamrolled a Texans team that remains tops in the AFC at 6-1.

Now, the old "it's not whom you play, it's when you play 'em" theory certainly applies in many instances. But this week, with the Packers' offense hitting high gear the last two games and the 1-5 Jaguars having just lost star running back Maurice Jones-Drew to injury, the timing of this matchup seemingly couldn't be better for Green Bay.

The Jaguars also come in ranked dead last in the league in total yards on offense and 28th on defense. They've lost three games by 17 or more points. But don't tell that to McCarthy, who likely is as aware of his middling record against the AFC as he is of his superb mark within his own division.

"We're not really big into the numbers," he said. "We're into the film. We're really emphasizing more film study this week, because of not playing these guys in the past."

McCarthy said he's not discounting the possibility of "unscouted looks," even in Week 8, because the Jaguars are still transitioning to first-year head coach Mike Mularkey. On film, the Packers also see a team that has lost two tough games in overtime, to Minnesota and Oakland, after squandering fourth-quarter leads. The Jaguars don't necessarily beat themselves, either. Their turnover ratio for the season is even, an unusual attribute alongside a 1-5 record.

Make no mistake, the Packers are on their guard. When asked this week if this was a "trap game" for the Packers, quarterback Aaron Rodgers pretended not to know what the term meant.

"They're a real disciplined defense," said center Jeff Saturday, who played the Jaguars twice per season for more than a decade as a member of the Colts. "They're kind of a bend-but-don't-break defense. They're not going to give you big plays. They're going to make you earn it all the way down the field."

That's the nature of the NFL. Every win is earned, a fact to keep in mind even more so against uncommon opponents.

"You never get overconfident, because any given Sunday anything can happen," safety Morgan Burnett said. "Those guys are professional athletes just like us. You take this game very serious, because this is our next opponent. Those guys are going to come in juiced up, ready to go."

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