The best offenses in college football are often teams that have workable plans to convert on third-and-long, so they can stay on the field and score points. The top offenses in S&P+ from year to year are generally good to great at passing downs (defined by Bill Connelly as second-and-long and third-and-medium or longer).

These moments are so crucial that some teams have had major success despite being just mediocre at everything on offense other than passing downs. 2008 Texas and 2015 Michigan State stand out in that regard.

A look back at three years of S&P+ passing-downs stats reveals the teams that manage to rank within the top 10 in converting passing downs have some of the following three key features.

Based on the last three years, teams that convert passing downs at a top-10 level either have a dual-threat QB ...

Obviously, it’s harder for a defense to play tight coverage and prevent scrambles at the same time. A QB who has broken contain and is running toward open grass with receivers breaking off routes to give him targets is the original — and probably still the most deadly — form of run/pass option.

On this third-and-6, you can see what made Penn State such a nightmare on passing downs over the last two years. The defense has to account for QB Trace McSorley’s quick legs and accurate tosses on the run, the check down to that Saquon Barkley fellow, and the talented group of receivers running their initial patterns.

If a defense can’t contain a QB like this with the pass rush, the defensive backfield is going to lose more often than not. There’s simply too much to defend, and it’s all happening too fast.

... or an NFL-grade tight end ...

Whenever people discuss Wisconsin’s Playoff chances, the conversation often focuses on the limitations of QB Alex Hornibrook. So you’d probably be surprised to learn that Wisconsin finished seventh in the country in passing downs on offense in 2017, despite relying on a rotating cast of underclassmen as the starting receivers.

This wasn’t due to too much overlooked brilliance on the part of Hornibrook, but to UW’s use of TE Troy Fumagalli as a cheat code to simplify third and long.

They would flex him out in spread sets, usually as the third receiver from the line of scrimmage, but occasionally as a flexed-out slot close to the sideline. Hornibrook could read where the safety help was coming and either hit 6’5, 250-pound Fumagalli matched up on some hapless DB or LB or throw to a receiver facing a one-on-one matchup.

In this case, the Hurricanes dropped a safety down to help the LB defend the seams from Fumagalli, and Hornibrook hit the receiver outside with a solid fade to the end zone.

Replacing Fumagalli is the story in Wisconsin this offseason, over any improvements by Hornibrook or their departures on defense. College defenses don’t have great answers for matchup nightmare TEs (the NFL doesn’t either), other than “send help,” which simplifies the coverage and the job for the QB and WRs to something like “one read, then pitch and catch.”

Btw, here’s NC State using hybrid Jaylen Samuels in a similar fashion, converting a third-and-17 to him up the seam:

... or multiple true threats at WR.

Fielding two 1,000-yard wideouts wasn’t that common of a way to generate a top-10 passing-downs offense in this sample, accounting for four of 30 occurrences. The idea is pretty straightforward, though.

Having one great wideout doesn’t threaten a defense too terribly much on third-and-long, because they already know where you want to go with the football. The defense can always send help to a single star WR, and even if he’s lined up in the slot, they can match up in dime without fear of being punished by his size.

So to consistently overstress a defense on third-and-long requires two receivers that defenses will struggle to cover. This is essentially the formula that a team with a great TE uses; they just often don’t use the TE in this fashion until third-and-long, because otherwise he’s helping to block much of the time.

When a team has two great wideouts, it can get up to all kinds of tricks that force defenses to make a choice about where to send help, then punish the choice.

Beyond the option of using one like a TE to attack the seam or to flood a zone, another strategy is to play these WRs to extreme ends of the field. With Oklahoma State in 2017, that was often with the shallow cross route combination, which allowed QB Mason Rudolph to “read” the dig-post route combo and throw a TD on the post to James Washington ...

... but he could also hit Marcell Ateman running a fade or comeback isolated on a CB, if the defense shifted its coverage over to stop the dreaded Washington post:

Out of 30 top-10 passing-downs teams, I found only four “exceptions” to these rules.

The 2017 NC State Wolfpack technically didn’t have an NFL-caliber receiving TE, but did have an NFL-caliber “fullback hybrid” in Samuels, whom they essentially used like a TE.

Then the 2017 Boise State Broncos, who didn’t quite have an NFL-caliber TE in Jake Roh (39 receptions for 410 yards and nine TDs), a dual-threat QB (at least not when Brett Rypien was on the field), or a second 1,000-yard WR after Cedrick Wilson. But considering the Group of 5 competition, Roh was comparable to an NFL TE, the Broncos regularly used other TEs along with him, and they’re generally one of the most creative play-calling teams in the country.

The 2017 Georgia Bulldogs were a sort of exception. They regularly used TEs who might prove to be NFL-caliber (Isaac Nauta, Charlie Woerner), but they didn’t throw to them terribly often. They didn’t put one WR over 1,000 yards, either. Their trick was to convert a lot of third-and-longs by checking into runs when they caught teams vacating the box or playing dime. With Sony Michel and Nick Chubb moving on while Jake Fromm returns, they’ll probably lean more on those TEs.

The 2015 Oklahoma State Cowboys didn’t have an NFL TE and didn’t quite have two 1,000-yard WRs, but that’s because they had three who were worthy, with Washington (979), David Glidden (866), and Ateman (766) splitting up the targets. OSU slipped out of the S&P+ passing-downs top 10 in 2016 after losing Glidden and Ateman, then climbed back in for 2017 when Ateman returned from injury.

A flex TE in the slot breaks down a defense by commanding help and attention in the middle of the field, where defenses don’t have their best coverage defenders. The scrambling QB does so by adding options and thwarting initially good defense. And third down becomes a huge problem for the defense if they need extra numbers in the pass rush and to cover two different receivers on extreme ends of the field.