You might not believe this even if I tell you and back it up with facts and remind you that I have nothing to gain by pulling your chain.

OK, here goes.

As you probably know, the Packers are 1-3 in quarterback Aaron Rodgers' past four starts, including January's playoff loss to the New York Giants. Here is what you might not realize: Over that stretch, the Packers' downfield passing offense has plummeted to the absolute bottom of the NFL's rankings.

That's right. At this moment, no team is having a harder time being explosive than the Packers. The Packers!

Anecdotally, I think we would all agree their offensive production has slowed since the Kansas City Chiefs ended a 19-game winning streak last December. But the drop in efficiency and production of their best attribute has been acute, and it continued into Sunday's season-opening loss to the San Francisco 49ers.

ESPN Stats & Information defines downfield throws as those that travel at least 15 yards in the air past the line of scrimmage. As the first chart shows, Rodgers' completion percentage has fallen by more than half in those situations to 25.8, and his Total Quarterback Rating (QBR) has dropped to 17.4 (on a scale of 0-100). Both figures are league lows for starters with at least 25 plays/attempts over that stretch.

In short, Rodgers and the Packers hit a wall at full speed and haven't recovered. They were setting NFL records for downfield efficiency during their winning streak, but most recently they were reduced to dumping off 20 of their 30 completions to receiver Randall Cobb and tight end Jermichael Finley (for a total of 124 yards) against the 49ers.

To be clear, a reduced ability to hit big plays shouldn't be a death knell for any team, even in a passing league. For the Packers, however, it has been their team-wide identity during one of the most successful periods in team history, and it has helped cover for deficiencies in other areas of the team. In response, the Packers must find an antidote or make substantive adjustments to their approach.

I don't expect that to be an easy job during a short week of preparation for an opponent, the Chicago Bears, that has stood up well against the Packers' downfield passing throughout Rodgers' career. As the second chart shows, Rodgers has a 65.7 passer rating on throws of 15-plus air yards against the Bears and a 102.7 passer rating against everyone else.

(Thanks to ESPN's Keith Hawkins, Jason Starrett and John McTigue for their research.)

Those are the facts. Naturally, the far more difficult task is understanding what has happened and how it can be fixed. There isn't likely to be one "magic bullet" answer other than to say defenses are prioritizing the deep pass and taking their chances with other aspects of the Packers' offense.

The 49ers, for one, used a secondary with exceptional man-to-man coverage skills, combined with deep safeties, to limit the Packers' downfield chances. They displayed little regard for the Packers' running game, and the Packers complied by calling only nine running plays (all to tailback Cedric Benson) and going without a running back on the field for more than half (31 of 61) of their plays.

"Their key thing was to keep us up front," said receiver Jordy Nelson, who caught five passes for 64 yards. "They don't want to give up any big plays. They did a good job of making us go the long way. That's tough against a defense like that. Going 10 yards at a time, three downs to get a first down. It makes it real tough on us. But it's going to be no different on Thursday. Chicago is going to do the same thing. They'll keep us in front."

Said Rodgers: "We didn’t have the opportunity to take a lot of shots downfield, but when we did, they made some plays on it."

Indeed, Rodgers directed three deep sideline passes in the first half of Sunday's game. None of them were ideal matchups. All were to receiver James Jones, who is talented but must be considered the Packers' third-best downfield threat after Nelson and Greg Jennings. Two of the passes fell incomplete, largely because Rodgers couldn't drop the ball into the tiniest of windows available because of coverage from cornerbacks Tarell Brown and Chris Culliver. On the third, Jones committed offensive pass interference to create space to make the catch.

(Jones did haul in a 49-yard pass in the fourth quarter to set up the Packers' final score.)

For the most part, the 49ers played their safeties deep and kept Nelson and Jennings in front of them. Case in point: Safety Dashon Goldson stymied one of the Packers' most successful downfield routes by diagnosing a play-action post to Nelson early in the third quarter.

To be clear, the 49ers might have the NFL's best defense. But even a moderate defense can take steps to take away a single weapon. If you were the Bears or anyone else, why wouldn't you play as deep as possible and challenge the Packers to beat you with short passes and a running game they sometimes ignore?

These are some of the questions the Packers must face in this short week. Do they still want to be a downfield team? Or did their extensive game plan for Cobb on Sunday indicate their planned response to defenses that sit back to take away the big play? And would that mean for a defense? Its margin for error is lower when not protected by an explosive offense.

Four games isn't a huge sample size. When it carries over from one season to the next, however, it's fair to call it a trend. But like all trends, it can be stopped, redirected or reversed. Let's see what the Packers come up with.