After six weeks of seemingly ignoring their weaknesses and overcoming all the little things that were supposed to drag them down, the Broncos finally succumbed to their flaws on Sunday night. The Colts put up yet another fearless, impressive performance against top-flight competition during the first 39-33 win in NFL history, but what put them above the Broncos was exploiting the problems that had been swept under the rug by the oppressive brilliance of Peyton Manning. With Manning struggling for large portions of Sunday’s game, the Broncos looked far more than mortal; they looked downright vulnerable.

It’s not that you couldn’t have seen these issues coming for Denver; it’s that they’ve been around and just haven’t mattered. Here’s what kept the Broncos from going 7-0:

1. The injuries to the offensive line. On Sunday, Denver was down three starting offensive linemen. Among the missing was star left tackle Ryan Clady, who signed a five-year, $57.5 million deal to protect Manning’s blind side. He was replaced by journeyman Chris Clark, who had put together an admirable stretch at the line’s most important position. Right tackle Orlando Franklin missed the Colts game with a knee injury and was replaced by guard Louis Vasquez, who was making his first career start at tackle. Another guard, Manny Ramirez, has played center all year after Denver’s top two choices in the middle, J.D. Walton and Dan Koppen, went down with injuries before the season. Denver has been able to get past those injuries with Manning using his legendary ability to read a defense at the line of scrimmage before the snap and then get the ball out quickly afterward.

That simply didn’t fly on Sunday. The Colts beat up the Broncos at the line of scrimmage, collapsing Manning’s pocket and forcing him to scramble or rush throws more frequently than has any other team during this 2013 campaign. The Colts knocked Manning down 10 times in this game; to put that in perspective, Manning had been knocked down seven times during the previous five weeks combined. Robert Mathis was an absolute terror, abusing Clark for most of the game on the left side of the line. The Broncos tried to throw in wunderkind tight end Julius Thomas as help for Clark, and Mathis made him look even worse, seemingly confirming the concerns about Thomas as a blocker. Mathis finished with two sacks and four hurries on his own, and his 11.5 sacks through seven games are tied for the fifth-highest total in that time frame since the league started tracking sacks in 1982.

The Colts, who had the league’s third-worst run defense through six weeks, did a better job against the run, partially because of the return of LaRon Landry. Knowshon Moreno managed a mere 40 yards on 15 carries, so if Landry can get that unit rebooted and playing sounder football, it will fill in the biggest hole in Indianapolis’s game.

This isn’t a problem that’s going to get much better for the Broncos. Clady, Walton, and Koppen are all on injured reserve. Franklin will be back, but even when he returns this is a patchwork line that has guys playing out of position and stretched into roles where they don’t belong. Manning and the scheme will mask some of their weaknesses, but there are a lot of teams that are going to be able to dictate terms up front and create problems for the Denver offense.

2. The absence of Champ Bailey (and Von Miller). The Broncos finally got Bailey back last week against the Jaguars after their star cornerback missed the first five games of the season with a foot injury, but he was unable to prevent Justin Blackmon from having a monster game. This week, Bailey went down with what seemed to be a recurrence of his foot injury midway through the second quarter and did not return. Denver had the league’s sixth-worst pass defense through six weeks per DVOA, and it took a couple of key drops on what could have been touchdown passes to keep Andrew Luck from having a career game; as is, Luck went 21-for-38 with three touchdowns and no picks. If Bailey misses more time, the Denver secondary is going to remain in shambles.

Miller, meanwhile, made his return last night after being suspended for the opening six games. You would expect him to be an upgrade on the likes of Nate Irving, and while Miller did have an early run stop, he had a relatively quiet game by his lofty standards. The Broncos need Miller to be a superstar, particularly as a pass-rusher, to help hide the issues with their secondary. He showed flashes of brilliance Sunday, but he’ll need to take over more frequently after Denver returns from its bye in Week 10.

The Colts exploited Denver’s no-name defense by expertly employing misdirection. They created two big plays this way with Darrius Heyward-Bey — one a toss-back pass where Heyward-Bey went in motion and then stopped before Luck tossed him a safe pass in the opposite direction for an 11-yard touchdown, and then a 30-yard run on an end-around in which Broncos safety Rahim Moore overran the play.

3. Penalties. The Broncos had been among the league’s more-penalized teams during their 6-0 start, but it had not really come back to haunt them; on Sunday, it did. Denver committed 12 penalties for 103 yards during the loss, including a pair of personal foul penalties for a total of 29 yards during the Indianapolis touchdown drive that gave the Colts a 33-14 lead in the third quarter. One of those personal foul calls belonged to Kevin Vickerson, who was later involved in one of the most controversial decisions of the evening, a roughing the passer call that saw Vickerson graze Luck’s back before the star quarterback (arguably) dived.

Penalties alone aren’t enough to bring success or failure at the pro level; the Ravens and 49ers were two of the league’s most-penalized teams a year ago, and they made it to the Super Bowl, while the Falcons perennially rank among the league’s least-penalized teams, and it hasn’t done them much good in the playoffs. The Broncos can win while committing a bunch of penalties, but it also very well might come back to haunt them in a game like this one, when they can’t afford to do so.

4. Fumbles. While Manning has only thrown three interceptions through seven weeks, the Broncos have a disturbing habit of putting the football on the ground. Their skill-position players had combined for 13 fumbles through six games, with several of those coming in key situations, notably inside the red zone.

On Sunday, they added four more fumbles to their ledger, and the ones they lost were extremely painful. Punt returner Trindon Holliday fumbled a punt in the first quarter, with the Colts recovering and scoring a touchdown on the next play. Manning was strip-sacked by Mathis, with Colts linebacker Erik Walden narrowly out of bounds when he recovered the ball, scoring a safety on the play. And, of course, the play that basically sealed the game for the Colts came when Ronnie Hillman fumbled on the 2-yard line with 3:15 left in a nine-point game, with Indianapolis recovering. Those three plays amount to a 16-point swing.

5. Manning’s arm strength. The little birdies wondering whether Manning can throw a deep ball had a lot to crow about last night. The Colts played tight man coverage across the board on Denver’s receivers and forced Manning to try to throw isolation routes and fades all night, trusting that their defensive backs would be able to make a play on the football or that Manning wouldn’t be able to find his receivers. Indy was (mostly) right; Manning eventually got his, but he spent much of the first three quarters lobbing up dangerous throws toward his receivers, many of which fell incomplete. Even some of his big plays, notably the game-long 49-yard pass to Eric Decker, were underthrown and required a great play from the receiver, a lucky miss from a Colts defender, or both.

The Broncos eventually adjusted by using pick plays to bust Indy’s coverage, but by then, it was the fourth quarter and they were down 33-17. Other teams will try to do this to Denver’s receivers and hope they can get pressure on Manning quickly enough to force him into desperate throws.

Let Luck Rule

Can you imagine being a Colts fan before the season and going through the time-honored tradition of marking down wins and losses on the schedule? “Yeah, we’re gonna beat the Raiders in Week 1, but it’s gonna be real close. We’ll lose to the Dolphins in Week 2, Tannehill is too tough. But then it’s time for a hot streak! We’ll manhandle the 49ers on the road in Week 3, then take care of the Jaguars in Week 4, and we’ll squeak one out against the Seahawks in Week 5. I don’t think we’ve got enough to beat the Chargers in Week 6, but hey, we’re definitely going to take out Peyton and his Broncos on Sunday night in Week 7.” Is there literally a single Colts fan who thought this sequence of events would happen before the season? Football is weird, man.

While the Colts were able to exploit the Denver weaknesses above, they contributed to this victory by building upon last week’s loss to the Chargers and actually granting Andrew Luck a few series without being shackled to a running game. It looked grim when they ran the ball on three consecutive plays to start the game, but the Colts gave Luck four first-half possessions when he got to throw the ball most of the time, with Pep Hamilton calling for 24 pass plays against four running plays. Those drives produced 24 of Indianapolis’s 39 points.

As much as the Colts like to talk about the importance of their running game and how meaningful it is for them to get Trent Richardson involved, the truth is that it’s mostly lip service. Running the ball does create the occasional shot downfield, but teams aren’t afraid of Indianapolis’s running game and don’t commit serious resources to stopping it. Donald Brown at least produces the occasional big play, but Richardson has been DOA since arriving in Indy. He finished with another typical day on Sunday, producing 37 yards on 14 carries. Richardson averaged 3.5 yards per carry and 62.1 rushing yards per game during his time in Cleveland; since coming to town, he has averaged 3.0 yards per carry and a mere 45.6 rushing yards per game. He also lost a key fumble in the fourth quarter that allowed Denver back into the game, giving the Broncos the ball on Indy’s 23-yard line. Forget not being worth the first-round pick that the Colts dealt for him earlier this year; Richardson is actively detracting from the Colts right now.

In all, Indianapolis is averaging just less than 4.0 yards per carry when it has run the ball on first-and-10, a figure that leaps up to 8.8 yards per dropback when it decides to throw. You can’t throw the ball on every first down — you do want some equilibrium to keep the defense honest — but it’s clear that Indy needs to throw the ball more frequently on first down to put itself in better second-down situations. The Colts called a pass play on 58.6 percent of their first-and-10s against the Broncos. Before Sunday, more than 56 percent of their first-and-10s had been running plays.

The one problem in suggesting that the Colts need to throw more on first down is that their best receiver might not be coming with them the rest of the way. Reggie Wayne went down with a noncontact knee injury on what would have been a touchdown pass with a better throw from Luck during the fourth quarter. The Colts weren’t exactly trying to pick up big chunks of yardage after he went out, but they ran eight plays for a total of one yard after Wayne limped to the sideline. Wayne’s injury wasn’t immediately diagnosed, but everything from the nature of the injury to Wayne’s reaction on the sideline suggests that it is a serious knee injury, if not specifically a torn ACL.

If Wayne is out for any length of time, it will be a new frontier for the Colts; Wayne was playing in his 189th consecutive game for Indianapolis. The last time he missed a game was during his rookie season in 2001; to put that in perspective, that game he missed (with a sprained PCL) saw the Colts lose to the 49ers, with Jeff Garcia throwing a touchdown pass to J.J. Stokes. It has been a long time.

Without Wayne, the Colts really don’t have a receiver with a ton of experience going over the middle and catching slants for first downs. T.Y. Hilton has a ton of potential, and Heyward-Bey has speed to burn, but they’re both wideouts who do their best work as downfield targets, not intermediate options. Instead, the workload will probably fall on tight end Coby Fleener, who has already been forced to play a bigger role with fellow starting tight end Dwayne Allen out for the year. It would be foolish to count out Luck — he might just scramble for 10 first downs a game if he can’t throw for them — but it’s hard to imagine the Colts losing Wayne and moving on without skipping a beat. In the end, they might need Richardson after all.

On Dirty Football

When the 5-2 Colts come back from their bye, they’ll be traveling to Houston to play the 2-5 Texans in a game that the Texans will need to win in order to have any prayer of claiming the AFC South for a third consecutive season. The Texans put in a good effort at undefeated Kansas City on Sunday before coming up narrowly short, losing 17-16, but the players they lost may prove to be more significant. Already without Matt Schaub, the Texans lost Arian Foster, Ben Tate, Duane Brown, and even J.J. Watt for stretches during Sunday’s game. The most damaging injury saw linebacker Brian Cushing suffer a broken leg and a torn LCL when he was taken out by a Jamaal Charles cut block, prematurely ending his season for the second consecutive campaign.

Let’s talk about that cut block, since I saw chatter during and after the game that it was a dirty play. That’s not the case. Charles’s cut block was totally legal and a regular part of the repertoire of any running back who has to stand up in pass protection against bigger, stronger defensive players. Part of being a defensive player is knowing that and protecting yourself against cut blocks; it’s hard to tell whether Cushing didn’t see Charles’s block until it was too late and/or whether Cushing’s foot got caught in the turf at the time of the block, but in either case, he wasn’t able to adequately protect himself from the hit and, unfortunately, suffered a serious injury. It’s worth noting that Cushing, after the game, sent Charles a tweet expressing no ill will with regard to Charles’s block.

The particular irony here is that the Texans, of course, are a zone-blocking team running a scheme that is famed for cut-blocking opposing defensive linemen. The cuts that the Texans make on their beloved outside zone stretch play free up the cutback lanes by taking out the pursuers from the backside, with little to no warning beforehand. There’s no karma in play, and it’s pretty stupid if you think that’s the case or somehow justifies the injury to Cushing, but the Texans are about as aware of the effects and consequences of cut blocks as any team in football. If the league wants to legislate the cut block out of the game, that’s one thing, but there’s no sense in getting angry at Charles for a clean block.

Keenum Separated

The one bright spot the Texans can take away from their loss is how quarterback Case Keenum played during his first NFL start. Playing against the league’s best pass defense on the road, Keenum made a number of big plays and went 15-of-25 for 271 yards, throwing a touchdown pass while avoiding any interceptions. Houston’s shot at a victory came up short when Keenum and his offensive line couldn’t handle big blitzes on three consecutive third downs in the fourth quarter, but Keenum showed a surprising amount of poise and promise for a player who had been written off as practice-squad filler before this weekend.

Was Keenum an improvement on Matt Schaub? In some ways, yes. Keenum’s mobility allowed him to get out of the pocket and create different angles for the defense to consider, something that was sorely missing with Schaub around. At his best, Keenum was able to pull off a pretty convincing Tony Romo impression, like he did on this 42-yard pass to Andre Johnson. And for a guy who supposedly didn’t have NFL arm strength, he made a number of passes that sure looked like he could make the throws he needed to make, like this 29-yard touchdown pass to DeAndre Hopkins.

What was most interesting was how the Texans installed plays that put Keenum in the shotgun and even occasionally in the pistol. Those moves hint at the bigger schematic change that could be to come for the Texans. As Chris Brown noted during the game on Twitter, the Texans even took things a step further.

Check out this 42-yard pass to DeVier Posey, most of which comes after the catch. It’s a simple packaged play with two primary options based off a simple read of the outside linebacker to that side, Justin Houston. If Houston contests the five-yard stick route being run by Posey in the slot, Keenum has the numbers to run the inside zone and hand the ball off to his running back. If Houston rushes the passer or contests the running play, it’s his job to throw Posey open; since the inside linebacker honors the run-action, he throws the ball inside and Posey makes a tackler miss.

Now, packaged plays aren’t anything new to the NFL, and I haven’t watched every Texans snap over the past few years, but I don’t think Gary Kubiak had this in his playbook for Schaub. It’s reminiscent of the offensive scheme Keenum ran in college, and it’s no surprise that Kubiak installed it to give Keenum a play he was experienced and comfortable running during a testing first start.

Here’s where it gets interesting. You can’t install a new offense overnight, nor would you want to. What you do need is the free time — say, a bye week — to install some new offensive concepts. Guess what the Texans have this week? Kubiak undoubtedly won’t want to scrap his entire offensive playbook and just run the spread, but if he’s going to keep playing Keenum, he’ll want to integrate the things that work from his zone-blocking rushing attack with some concepts and plays from the playbook Keenum worked with at the University of Houston. Keenum’s first year of action in college came under the tutelage of Art Briles, who would leave after the year to become the head coach at Baylor. A quarterback who had signed a letter of intent to play under Briles (and compete with Keenum) in Houston then decided to follow Briles to Baylor instead. That quarterback was Robert Griffin III. And when Griffin entered the draft in 2012, guess who drafted him? Mike Shanahan, who then integrated aspects of the attack Griffin ran at Baylor with the same zone-blocking scheme that he instilled upon Kubiak during their time in Denver together. I would not be surprised one bit if the Texans spent this bye week cutting up Washington tape and installing stuff from that playbook for Keenum to run against the Colts after the bye.

This all depends, of course, on the Texans leaving Keenum in as the starter against Indianapolis. I think, at this point, it’s the right move. You certainly can’t fault Keenum for how he played, given the circumstances and the quality of the opposition. He’s a higher-variance option, and if the Texans were to install a new bunch of plays that the Colts haven’t seen on film during the bye, it would be a pretty clever David strategy. There’s also the perception issue. Kubiak can keep Keenum in there without having to “bench” Schaub, just by claiming that Schaub isn’t 100 percent or suggesting that Keenum won the job while Schaub was hurt. If Keenum plays poorly, he can go back to Schaub by pointing out that he’s the best quarterback on the roster. If he goes back to Schaub against the Colts, the home crowd is going to start screaming for Keenum the moment Schaub misses a throw, and it’s not going to stop until it gets what it wants. And then, when Kubiak benches Schaub, he really can’t go back. The Texans are stuck with Keenum for now. Let’s see what they try to do with him.

Seventh Heaven

And then there are the Chiefs. At 7-0, they are the league’s only undefeated team, a fate that even the rosiest Chiefs backer could not possibly have fathomed before the season. These Chiefs have a simple game plan that invokes the tenets of the last great surprising Alex Smith–led team, the 2011 49ers. That’s a list that reads something like:

1. Do no harm: Avoid turnovers at all costs.

2. Beat up the opposing quarterback and wait for him to make a mistake. Catch that mistake.

3. Dominate the field-position battle.

4. Don’t get injured.

5. Play an easy schedule.

The Chiefs have done all of that in spades so far. Sunday was the first time they lost the turnover battle in a game; even after doing that, they lived to tell the tale and their turnover margin is still plus-11. This time last year, the Chiefs were minus-18 in the same category. They have 10 interceptions this year after recording just seven all season a year ago. Kansas City had the league’s best average starting field position difference heading into Week 7, at a full 13 yards; that will drop this week, but the Chiefs still had a six-yard difference between their average starting field position and the Texans’ on Sunday.

The last two are the tougher ones to sustain. The Chiefs have had a total of 10 missed games from their starters through seven weeks, four of which were from the relatively inessential Anthony Fasano. The last time the Chiefs were this healthy was, well, their surprise division-winning season of 2010. There’s no reason to think the Chiefs will suddenly see five players get injured in a week to come, but they’re unlikely to remain this healthy going forward, and health has been a huge advantage for a top-heavy, star-driven roster.

They’re a team that is incredibly dependent upon Jamaal Charles, with no viable replacement for him on the roster. Charles leads the league in touches and plays virtually every down, as his backup is fumble-prone rookie Knile Davis. This is a very risky strategy, but I’m not sure the Chiefs are necessarily wrong to give Charles a heavy workload. Remember that the previous regime in Kansas City really went out of its way to limit Charles’s touches during that spectacular 2010 campaign, even when he was averaging nearly twice as many yards per carry as Thomas Jones did. It kept Charles’s workload down to 17.2 touches per game, but the following year, Charles tore his ACL in Week 2 anyway. This year, the Chiefs are giving Charles the ball 24.4 times per game, and it wouldn’t be a surprise to see that number rise. They could be more judicious about finding times to rest Charles — pre-halftime draws seem like a good starting point there — but with the shelf life of running backs already limited, it seems smart to run Charles out there while the Chiefs can.

And while the schedule remains pretty easy, it’s not going to stay that way for long. Kansas City still gets to host the Browns and travel to Buffalo before its Week 10 bye. After that, it has a home-and-home with the Broncos sandwiching a game against the Chargers. It’ll travel to San Diego to end the season, but before that, it hosts the Colts in what could very well be a matchup to determine AFC playoff seeding.

So, does that mean the Chiefs are some kind of incredible fluke, a confluence of one great player and a dominant defense and a bunch of cream puffs being served up for slaughter? Take a step backward, Mercury Morris: No. The Chiefs have weaknesses, but they’re a genuinely good football team. At 7-0, we’re past the point of flukiness for good. Of the 30 previous 7-0 teams since 1970, the Chiefs’ point differential of plus-88 ranks 19th; not exactly otherworldly, but well within the sample. Among the teams that had an inferior point differential to this year’s Chiefs — teams that would presumably not be as good — are the perfect 1972 Dolphins (stay back, Mercury), the Super Bowl–winning 1990 Giants, and the 2006 Colts team that won Peyton Manning’s only Super Bowl.

It seems pretty clear that, barring an unexpected (but entirely possible) loss to the Browns or Bills, everyone will wait to judge the Chiefs until they travel to Denver in Week 11. If you had to think of a team that was built to beat the Broncos offense, this Chiefs defense would represent a great example. My concern is that Denver’s passing defense is its biggest weakness, and Kansas City might not be able to exploit that with Smith and his relative lack of receiving options. For Chiefs fans, the worst-case scenario of a wild-card berth probably doesn’t sound too bad. Following a 2-14 season with a 7-0 start sure felt improbable, but the Chiefs are making more believers inside and outside of the league with each victory. The Chiefs are back.