Awful offensive line play and quarterback injuries are the two quickest ways for a football team's season to fall apart.
The Indianapolis Colts have endured both in stumbling to a 3-9 record.
With franchise QB Andrew Luck out for the year due to shoulder surgery, young Jacoby Brissett is learning on the job. Brissett has a big arm, ideal size and he moves well.
But the Colts' offensive line struggles hinder his development.
Indianapolis has given up a league-high 51 sacks. That's on pace for 68 for the season, which would be second worst in the NFL in the past 10 years and tied for fifth worst in the last 20 years. (The 20-year low is 76, allowed by the expansion Houston Texans in 2002.)
Here's a subjective ranking of the NFL's worst offensive lines this season:
1. New York Giants. The Giants lead the NFL in three-and-out drives and are 27th rushing. Eli Manning makes the sack numbers look respectable but tackles Ereck Flowers and Chad Wheeler have been poor. Injuries have taken out Wes Richburg and D.J. Fluker. They're second worst in the league in running on third and 1 or 2 (8 of 18).
2. Houston: The Texans are 29th in sacks allowed and have yielded the most pressures in the NFL (17 a game), according to Pro Football Focus.
3. Indianapolis. The Colts are 28th in rush average and 29th in three-and-out drives. A season-ending injury to guard Jack Mewhort didn't help.
4. Arizona: The Cardinals are 32nd in rushing yards and rush average. Injuries to the two best linemen (Mike Iupati and D.J. Humphries), plus a lot of downfield passing has hurt pass protection.
5. Cincinnati: The Bengals were decimated by the free-agency loss of tackle Andrew Whitworth and guard Kevin Zeitler. The Bengals are 30th in rushing and rush average and last in time of possession.
Dishonorable mention: Denver, Chicago, Seattle and Detroit.
Colts vs. blitz: The Colts' young offensive line has struggled with post-snap adjustments and communication. Eight of 12 sacks the past two weeks have come against the blitz.
"When people smell blood in the water, you've got to put fires out," said Colts coach Chuck Pagano, channeling metaphors. "If you don't put fires out, they're going to keep coming until you stop it. That's on us."
In seven drafts from 2009 to 2015, they got just two competent O-linemen (Anthony Castonzo in the first-round in 2011 and Mewhort in the second round in 2014).
In 2016, they drafted three O-linemen. First-round center Ryan Kelly of Alabama looks promising. Third-rounder Le'Raven Clark has struggled. Fifth-rounder Joe Haeg shows some promise but is inconsistent. Meanwhile, left guard Jeremy Vujnovich and right tackle Denzelle Good are liabilities.
The 30,000-foot view: Colts General Manager Chris Ballard, hired in January, is in a similar spot as Buffalo counterpart Brandon Beane in the sense he must make up for years of poor drafting. The Colts opened the season with just 21 of their own drafted players on their roster, second fewest in the NFL (to Buffalo, which had 16). The difference, of course, is Ballard has Luck, presuming the star QB fully recovers from shoulder surgery 11 months ago.
In the last seven years, Indianapolis has devoted just one pick in the top two rounds to a front-seven player (bust Bjorn Werner in 2011). The Colts have not drafted a front-seven defender who has starred for them since Robert Mathis in 2003. That counts 33 front-seven draftees; not one a high-level starter. (In 2010, they took Jerry Hughes, who was unproductive in Indy but has turned into a star for the Bills).
Game-breaker: T.Y. Hilton. He ran the 40-yard dash in 4.34 seconds in 2012. Only four receivers at the combine have run faster than 4.30 in the past 10 years.
Weak links: Offensive line and defensive backfield. The Colts have just five healthy cornerbacks this week, and they've combined for four starts. Three are rookies.
Blown leads: The Colts have blown four double-digit, second-half leads this season. Those came in losses to Arizona (16-13), Cincinnati (24-23), Pittsburgh (20-17) and Tennessee (20-16).
"You have to finish," Pagano said. "When it gets to be crunch time, we seem to make some critical mistakes in critical situations. Whether it's third down or red zone . . . late turnovers, especially in your own end of the field. It costs you."
Key injury: The Colts rank 13th against the run. Defensive linemen Johnathan Hankins, Al Woods and Jabaal Sheard are playing well. But the Colts' run front took a hit Tuesday when top linebacker John Simon (neck) went on injured reserve.
Stat for the road: Colts place-kicker Adam Vinatieri, who turns 45 on Dec. 28, has the best percentage in the NFL over the past four years (104 of 112, 92.9). He's No. 2 in NFL history in points scored and field goals made, behind only Morten Andersen, who played until age 47. However, Vinatieri is just 11 of 20 kicking in Orchard Park, by far his worst venue.
Story topics: Indianapolis Colts