GREEN BAY—For an explanation as to why the Packers rank 28th in the league in pass defense, start at the end and work your way back.

Late in games is when Green Bay is surrendering big yards through the air, a disturbing trend that seems to have no sensible explanation.

Safety Morgan Burnett has been back for the last two games heading into Sunday's matchup with the Cleveland Browns at Lambeau Field. The run defense has become the unit's strength, forcing teams to throw, so the Packers know what's coming. Yet neither development has helped.

Here are the numbers, and they don't paint a pretty picture: Through five contests, on drives that began in the final third of the game (the last five minutes of the third quarter or anytime in the fourth quarter), opposing passers have an otherworldly 147.8 passer rating against Green Bay. They've completed 47 of 60 passes (78 percent) for 688 yards and six TDs without an interception.

The beginning two-thirds of the game? Different story. The opposing passer rating is only 88.3. The Packers have given up just 883 yards and five TDs in the first 40 minutes of games, with two interceptions. The completion percentage is nearly 20 points lower (71 of 121, 59 percent).

So what gives?

"We really don't know," safety M.D. Jennings said. "The biggest thing is we just have to try to finish better. I really don't know what it is. I wish we knew where we could pinpoint it and it's easy to fix. The only thing I can say is we have to finish better."

It's fair to point out that both Washington's Robert Griffin III and Detroit's Matthew Stafford piled up some numbers late in their losses at Lambeau Field that didn't impact the game's outcome. True enough.

But take out those "garbage time" stats and the collective late-game passer rating compiled by San Francisco's Colin Kaepernick, Cincinnati's Andy Dalton and Baltimore's Joe Flacco actually goes up, to a near-perfect 155.8 (22 of 27, 415 yards, three TDs, no INTs).

Granted, those numbers represent a smaller sample size, and over the next two weeks the Packers will face quarterbacks in Cleveland's Brandon Weeden and Minnesota's Josh Freeman that lack the pedigree of Green Bay's opponents to date.

But any NFL passer is capable of getting a hot hand, and the late-game struggles to defend the pass have altered Green Bay's games in the blink of an eye.

The last two road games have been particularly troubling. Trailing 30-21 early in the fourth quarter, the Bengals marched 95 yards in just seven plays – with 76 yards passing – in jump-starting their comeback.

Then last week, trailing 19-10 with under three minutes left, the Ravens' Flacco completed a 63-yard bomb on fourth-and-21 and then connected on an 18-yard TD pass one snap later. Two plays, 81 yards, and the Packers were holding on for dear life.

"Take away a play here or there, and we have a couple dominant performances," cornerback Tramon Williams said. "We want to get that dominant performance."

What the Packers need, and the sooner the better, is for the defense to close out a win at crunch time, when the pass is coming and it must be stopped.

"We definitely need to finish," linebacker A.J. Hawk said. "We need to find a way to put games away, especially last week. We let that thing get really close and it almost got away from us."

The offense had been scuffling in late-game situations, too, until two weeks ago against Detroit, when it put together a pair of field-goal drives in the fourth quarter to extend the lead. Then last week, the offense consumed seven minutes and 35 seconds of the fourth quarter to drive for a field goal and then killed the last 2:04 with a pair of first downs to seal the win in Baltimore.

That side of the ball has begun making clutch plays down the stretch. The other side needs to now, too.

"It's something we work on, but you can work on things all week, and if you don't take it to the field, it means nothing," Hawk said. "For us, we need to prove that on Sundays. We have to take it to the field if we want to prove we can play four quarters."

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