Does late-season momentum matter in the NFL playoffs? The Ravens hope so

NFL coaches have always made it a point of emphasis to get their players peaking down the stretch of the regular season. The theory is the strongest teams in December are best positioned to continue to excel in January.

Bill Belichick said it this way: “What happens will be determined by what happens in the next five weeks (December). This is where this team and every other team will define itself.”

The objective data hasn’t been cooperative in supporting this seemingly intuitive theory. A decade ago, the AP concluded, “The idea that a strong regular-season finish is a prerequisite for an NFL championship turns out to be one of the myths and misconceptions about the last month of the year.”

And last year, an extensive study by The Athletic’s Peter Keating and Jordan Brenner looked at all playoff teams since 2000 and summed it up this way: “…momentum is a myth, at least when it comes to predicting NFL playoff success.”

To define momentum, Keating and Brenner looked at how teams performed in December relative to prior performance. In other words, if your record was strong in December but no stronger than previous months, you were deemed to have no momentum. You had to be playing better down the stretch.

Can coaches like Belichick, who won six Super Bowls in nine appearances as a head coach and two more as a coordinator, be so wrong?

Are we even debunking momentum? Is the issue really analogous to the hot-hand theory, something similarly debunked before that debunking was debunked? Or does playing at a peak level in December simply mean the team is healthy, with coaching and game-plan execution firing on all cylinders?

Let’s take another look at the data and focus on one stat — point differential. (Note: I limited the time frame to the past six seasons — 2019-2024 — only because I had to pull the data mostly by hand.)

Did the top playoff teams in point differential in Weeks 14-18 perform much better than the teams that were the worst in the statistic? We could look at postseason performance relative to the point spread, but December performance is baked into that. We could adjust for home field, whatever that’s worth today, but that edge is rather small. Also, if you look at everything, you just end up recreating what actually happened and gain no predictive insight. In other words, every model needs outliers.

Here’s the chart of the top 10 teams in point differential and the bottom 10 teams (2019-2024 — Weeks 14-18).

P GAMES = Playoff Games; P WIN = Playoff Wins; P LOSS = Playoff Losses

The top 10 teams in point differential are 13-8 in the postseason, with the 2024 Baltimore Ravens still alive and able to change that total this weekend in Buffalo. The bottom 10 teams are 3-10, with the 2024 Houston Texans playing in Kansas City in the upcoming divisional round. No bottom 10 team has won two playoff games. Four of the top 10 have won at least two, with the 2020 Tampa Bay Buccaneers winning the Super Bowl.

Interestingly, the Kansas City Chiefs made the top end of the list only once, in 2021 when they lost in the AFC championship game to the Cincinnati Bengals. This year the Chiefs, at plus-5 in the span of Weeks 14-18, are ranked next to last among the remaining teams, though their divisional-round opponent (Houston) was last. Yes, the Chiefs sat starters in Week 18, which is a challenge with this data. Here is how all the remaining playoff teams fared:

• Baltimore Ravens: 94
• Philadelphia Eagles: 58
• Detroit Lions: 42
• Buffalo Bills: 24
• Los Angeles Rams: 17
• Washington Commanders: 14
• Kansas City Chiefs: 5
• Houston Texans: -20

The big takeaway is the Ravens are very formidable and the Texans are the easiest matchup in the divisional round. There’s no real edge here, given the odds. The Ravens are favored on the road against the Bills, though barely, with the game basically a pick ’em affair. The Chiefs are up to 8-point favorites as of Thursday, the second-biggest favorite of the weekend, despite Kansas City hardly being a powerhouse in December themselves.

The Ravens made the top 10 list in 2020 and won only one playoff game. They made the bottom 10 in 2022 and were bounced in their first postseason game.

Baltimore’s opponent, Buffalo, is coming off a dominant performance against the Broncos. The Ravens continued whatever they had gained in December by thumping the Steelers in a game not as close as the 14-point margin.

But the predictive limits of this data were illustrated in the wild-card round, where one of the top 10 teams of the period, the Bucs (plus-78 from Weeks 14-18), lost to the Commanders (plus-14) in overtime. Tampa Bay’s late-season surge proved unsustainable.

Still, the best teams in the metric have a .619 postseason win percentage vs. .230 for the worst teams. That certainly seems to validate the belief that December performance does have some carryover effect into January and is not merely recency bias — a cognitive bias where we remember and prioritize only the most recent information. That seems to bode well for the Ravens’ chances to advance to the championship round in Buffalo on Sunday.

(Top photo of Lamar Jackson, Derrick Henry: Alex Slitz/Getty Images)