ESPN put together an interesting study that ranked each NFL coach based on their fourth-down calls. Per the article, the number of fourth-down errors has plummeted each of the past four seasons. We’re learning!
Coaches have long viewed fourth downs as “what if we don’t get it?” as opposed to “why wouldn’t we gain one yard?” Look at the Rams/Packers game this past week. Sean McVay goes for it on 4th & 1 from his 29-yard line. Los Angeles didn’t convert. They ended up surrendering a field goal on defense and would score a touchdown on the next drive.
I’d be willing to bet that sequence, where you allow a field goal after failing to convert, would be the second-most frequent outcome after, you know, picking up the yards needed on fourth down.
ESPN’s timeline for their study started during Kyle Shanahan’s first season. Here’s how they determined their process:
We relied on three metrics from the ESPN Analytics team:
Total win probability sacrificed through fourth-down errors
Difference in expected fourth-down conversion rates vs. actual rates
Non-obvious fourth-down error rate
These metrics are shown as per-season averages and measure whether the coach’s decision agreed with our analytics model (accounting for two-thirds of the final ranking) as well as success in running fourth-down plays (one-third). All 32 coaches were sorted on those metrics and then those rankings were used to create the final order.
Per RBSDM, since 2017, the 49ers are smack dab in the middle from an EPA per play perspective on offense and defense:
I wouldn’t blame Shanahan for being conservative on fourth downs based on the 2017 roster. However, I feel the opposite this season when you factor in the offensive line, playmakers, and strong defense. Also, Jimmy Garoppolo is superb at quarterback sneaks. He converted a 3rd & 2 last game.
Here’s what ESPN had to say about Shanahan:
27. Kyle Shanahan, San Francisco 49ers
Years covered: 2017-21
Win probability sacrificed on fourth-down errors: 25% (Rank: 19)
Difference in expected vs. actual fourth-down conversions: -7.5% (Rank: 25)
Non-obvious fourth-down error rate: 26.8% (Rank: T-21)
Most notable fourth-down call: Trailing 7-0 in the first quarter against Arizona in Week 5, the Niners quickly drove deep into Cardinals territory with a chance to tie it up. But quarterback Trey Lance was stopped at the goal line on fourth-and-goal at Arizona’s 2-yard line. On the play, Lance took off for the right corner of the end zone but was greeted by multiple Cardinals and stopped just short. It was San Francisco’s first red zone trip of the season that didn’t result in a touchdown in a game the Niners would eventually lose by seven points. — Nick Wagoner
If we isolate this season, the 49ers have converted 57% of its fourth downs, which is tied for 12th in the NFL. Yet, surprisingly, they are fifth in EPA per play on offense on fourth downs. Shanahan has been aggressive, and it’s paid off.
There have been a couple of occasions where the math made sense to go for it. The first possession against Jacksonville comes to mind after a 48-play drive to begin the game. The last thing you want to do is settle for a field goal. I give credit to Shanahan for admitting he let his emotions get in the way.
Trailing against Arizona in the second game, it was 4th & 13 from Arizona’s 39-yard line. The score was 31-14. You need to score three times in the quarter. Shanahan elected to punt. The probability of you getting the ball back three more times in Arizona’s territory was slim.
The Cardinals ended up punting and only taking two minutes off the clock. Unfortunately, that does not mean the 49ers made the correct decision. Too often, these choices are validated based on the result. The 49ers would never again make it into Cardinals' territory after they settled for a field goal on the ensuing drive.
Still, knowing how far Shanahan has evolved his thinking on fourth downs, the future appears to be bright for maximizing possessions.