Aaron Rodgers and the Green Bay Packers went into AT&T Stadium as 3.5-point underdogs Sunday night and quickly blew out the Dallas Cowboys.

Then the rest of the game happened.

The 24-0 lead the Packers built by the early third quarter slowly fell apart — until, with 10:29 left on the clock, Dallas Cowboys quarterback Dak Prescott got the ball with a chance to cut it to just one score. Had Prescott not promptly thrown his third interception of the game, the Packers might not have left Dallas with their fourth win in five games. The Packers now sit alone atop the NFC North — but a primetime national TV audience saw a performance that continued a bizarre seasonlong pattern: a dominant first quarter and a dormant fourth.

So far this year, the Packers have scored 42 first-quarter points (ranked third in the NFL), 40 second-quarter points (seventh) and 28 third-quarter points (12th). But they’ve scored only 9 points in the fourth quarter (30th). That makes them the fifth-most volatile scoring team in the NFL, in terms of scoring by quarter. And of the top 10, they’re the only team whose scoring variance comes from faltering in the fourth quarter.

Why are the Packers starting so fast and finishing so slow? Because that’s how Rodgers is playing. Pro-Football-Reference.com’s splits show that Rodgers’s quarter-by-quarter production has mirrored his offense’s output:

Rodgers is less effective at the end of the game Quarter-by-quarter passing splits for Aaron Rodgers, 2019 season Quarter Att. Cmp% Yds TD Int QB rating yards per attempt adj. yards per attempt First 45 77.8% 483 3 0 133.6 10.7 12.1 Second 54 55.6 325 2 0 85.8 6.0 6.8 Third 38 55.3 247 1 0 84.0 6.5 7.0 Fourth 43 62.8 252 0 1 69.1 5.9 4.8 Source: PRO-FOOTBALL-REFERENCE.COM

If he existed all by himself, First-Quarter Aaron Rodgers would own or share the best completion rate, interception rate, passer rating, raw yards per attempt and adjusted yards per attempt in the NFL. Fourth-Quarter Aaron Rodgers would rank 25th, 22nd, 32nd, 32nd and 33rd, respectively.

Though there’s been quite a bit of analysis around whether Rodgers is actually clutch, being consistently bad in the fourth quarter is a new thing for him. Across his career, Rodgers’s quarter-by-quarter rate stats have been quite steady. Looking further at situational breakdowns this season, there’s no smoking gun for this recent development: Leading or trailing, on one side of the field or the other, Rodgers’s stats have been steady and solid until late in the game. In fact, the only clear area of concern is from within 10 yards of his opponents’ end zone — and going 6-of-15 on goal-line throws doesn’t explain why he’s put up numbers like the GOAT in five opening periods and a goat in five finales.

It doesn’t seem to be an issue with the supporting cast, either. Running back Aaron Jones had his second 100-plus-yard game of the season against Dallas, and the defense has allowed the eighth-fewest points. Rodgers thinks they’re more than the sum of their parts, too: He said after the game they “have that chemistry” that they’ve “been lacking the last couple of years.”

As FiveThirtyEight staff writer Josh Hermsmeyer explored this offseason, Rodgers’s once-historic levels of efficiency and effectiveness have dropped in recent years, especially with intermediate throws and play-action passes. Several analysts have noted that his longtime tendency to throw the ball away rather than risk throwing an interception now seems to be yielding negative returns. After Week 5, Rodgers ranks 22nd in passer rating, 25th in touchdown rate, 14th in QBR and 15th in net yards per attempt.

In the same postgame comments, Rodgers dismissed concerns about the offense not scoring late against Dallas by emphasizing the team’s win rather than his own numbers. “Days like today aren’t the best statistical games for myself, but I feel like [I] played my best game,” he said. “The way I kept moving and seeing things. I’ve accomplished a lot statistically in this league. I just want to win now.”

But even this doesn’t make sense. If Rodgers were choosing to focus on winning instead of excelling statistically, he wouldn’t be putting up monster first-half numbers and floundering toward the end, when opponents are trying to claw back into the game. If anything, it would be the other way around.

Maybe it’s late-game play-calling under new head coach Matt LaFleur. Maybe Rodgers is mentally struggling to make easy throws and run out the clock after years of winning with deep downfield strikes. Maybe age and injuries are sapping his stamina. Whatever the reason, the high-flying Packers might only be able to maintain their cruising altitude if the defense keeps making up for Rodgers running out of gas.

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