The universe has a funny way of timing things. The same week the world lost legendary rocker and Super Bowl XLII halftime performer Tom Petty, the Denver Broncos went into their bye looking like any number of Petty’s songs could eventually serve as the soundtrack for the 2017 season.

At 3-1, coming out of an early Week 5 bye, the 2017 Denver Broncos season certainly feels like anything is possible.

Denver has started 3-1 or better now four seasons in a row, including this one, with final results as varied as a Super Bowl title and missing the playoff altogether. Where this season ends depends on which Petty song they most closely resemble from here on out.

With a pair of division victories already in hand – including one against preseason AFC West favorite Oakland – there’s certainly the potential for good things waitin’ down the road for Denver. But with a friendly stretch of four-of-five home games to open the season, and last season’s collapse after a perfect 4-0 start, there’s ample reason to be concerned that the Broncos could be free fallin’ in the standings as the season wears on.

If the Broncos are going to avoid a breakdown like they suffered in 2016, it will be because the defensive front seven won’t back down and because offensive coordinator Mike McCoy starts runnin’ down the dream of an AFC West title.

“I Won’t Back Down”

Last year, pretty much the entire NFL world was pushing around the Denver Broncos defensive front seven. On 10 different occasions Denver allowed 120 or more rushing yards; they were 5-5 in those games. They twice allowed more than 200 yards, losing both games to divisional opponents (Oakland and Kansas City). It’s no coincidence that Denver ranked 28th in rush yards allowed and 28th in average time of possession. Opponents kept the ball out of Denver’s hands by keeping it on the ground against them.

The offseason additions of nose tackle Domata Peko and defensive end Shelby Harris, coupled with the emergence of second-year end Adam Gotsis, have shored up many of last year’s deficiencies. Derek Wolfe continues to be one of the top run-stopping interior defenders in football, and opponents can no longer exploit the gaps opposite him as they did last year. Brandon Marshall and Todd Davis now have a full year of working together as the second line of run defense, and that chemistry is beginning to show.

Through four weeks, Denver led the NFL in rush yards allowed by a wide margin. Their 50.8  yards allowed per game heading into the bye were a full 20 yards better than second-place Philadelphia at 70.8. The longest run they’ve allowed, 21 yards by the Chargers’ Melvin Gordon, came on the very first play of the year from scrimmage. They’ve shut down Gordon, Ezekiel Elliott, LeSean McCoy and Marshawn Lynch – each a high-quality if not elite back.

In each of their last two Super Bowl seasons (2013 and ’15), the Broncos boasted a top-five rushing defense. The “No Fly Zone” may get the headlines and magazine covers, but it was built on the back of a solid run defense and pass rush. Aqib Talib, Chris Harris and Company are at their best when Von Miller and whoever is on the edge opposite him (DeMarcus Ware, Shane Ray, Shaquil Barrett, et al) are getting after the the quarterback. And it all starts with Wolfe and the big boys up front stopping the run.

If Denver is going to rekindle their Super Bowl aspirations, it will be because the defensive front seven stands their ground and won’t back down in the run game.

“Breakdown / Free Fallin'”

At the quarter mark of the 2016 season, it looked like the Broncos were learning to fly under second-year quarterback Trevor Siemian. With perfect 4-0 record and scoring 27.75 points per game, Denver was rolling into the great wide open. But Siemian was headed for a breakdown.

The injury he sustained in a Week 4 win at Tampa Bay would plague him for the rest of the season. Denver went just 5-7 following Siemian’s initial injury. There was no more apparent manifestation of his left shoulder AC joint strain than in a Week 6 loss to the Chargers on Thursday Night Football when Siemian failed to even get the ball into the end zone on a hail-Mary pass on the game’s final play.

As the Denver run defense struggled to keep opposing offenses off the field, the battered Siemian got little help from his own run game when C.J. Anderson was lost for the season after Week 7. Give credit to then-rookie Devontae Booker, who played admirably as the No. 1 option when Anderson went down, but with limited depth behind him in Kapri Bibbs and Juwan Thompson (neither of whom are on the roster this year) it was a heavy burden for Booker to bear.

A soft run defense, Siemian’s shoulder and no appreciable run game to speak of had Denver in a nosedive through the second half of the season. Were it not for a miraculous special teams play in Week 9 in New Orleans and an injury to Derek Carr in Week 16, Denver very well could have gone 1-7 down the stretch instead of 3-5 and finished below .500. As with their win in Week 1 thanks to a missed last-second field goal, plenty of people were saying, “You got lucky” to finish with a winning record.

If Denver is going to avoid free fallin’ like last year, they must keep Siemian from breaking down; that starts with relying more on the run game.

“Runnin’ Down a Dream”

There’s a common thread in each of Denver’s three victories through the first quarter of the 2017 season: When Denver runs the ball consistently, they win.

In all three victories to date, Denver has run the ball at least 30 times and with a greater frequency than Siemian threw it. In their only loss, Siemian threw almost twice as many passes (40) as McCoy put the ball in his running backs’ hands (23).

In 2016, Denver was 6-1 in games in which they ran the ball 30 or more times. They were 0-5 in games they had fewer than 20 rush attempts. They were 5-1 when they ran the ball more than they threw it. And that was without Anderson for half the season, or the offseason additions Denver made to the backfield this year.

For as thin as Denver was at running back in 2016, they’re equally deep this season. Anderson ranked fourth in the league with 330 rushing yards through Week 4. Offseason free-agent acquisition Jamaal Charles, while not putting up huge numbers in total through four games, entered the bye fifth in the league with 5.3 yards per carry and looking close to returning to full form. (Anderson is no slouch at 4.5 YPC himself, for what it’s worth.) Booker has seen only limited action as he recovers from a broken wrist this offseason, but he offers a quality option behind both Anderson and Charles should either one of them have setbacks. And head coach Vance Joseph has still yet to unleash a potential secret weapon in speedy rookie De’Angelo Henderson.

Denver has depth for days at the running back position, and clearly the offensive line is a better run-blocking unit than they are in pass protection. Siemian has already been sacked 13 times this season; that’s an average of 3.25 per game. (Last year Denver QBs were sacked an average of 2.5 times per game, putting them in the top 10 for sacks allowed.) If Siemian continues to take that kind of punishment, it could be only a matter of time before he suffers another injury and another free fall ensues. Joseph and McCoy can mitigate that risk by leaning more heavily on a rushing attack that was tied for 10th in the league in yards per attempt through four weeks.

Denver’s best chance of making the playoffs will come if they’re runnin’ down that dream, not trying to pass their way there.

“The Waiting”

The Kansas City Chiefs are clearly the class of the AFC West – and the conference on the whole. While many were quick to anoint Oakland the favorites in the division, Denver showed last week (and Baltimore helped show Sunday) that the Raiders aren’t the stalwart so many expected them to be.

The Broncos have a pair of winnable games – vs. the Giants and at the Chargers – before a crucial Week 8 matchup with the Chiefs in Kansas City.

Through four weeks, it feels like anything is possible for this Broncos team. There are similarities to the 2015 team that won it all, and likenesses to the 2016 squad that crumbled down the stretch.

Which team will they ultimately resemble at season’s end? That depends on which Petty anthem script they follow.

As it is every time the bye week rolls around, the waiting is the hardest part.

With the bye now in the rearview mirror, the answers will come around here very soon.