An NFL team has to be good to get to 12-1. Bad teams don’t win 12 out of 13 games. But not all 12-1 teams are created equal.

A team like the 1985 Chicago Bears might dominate its opponents week after week, winning by scores such as 44-0, 36-0 and 45-10. But another 12-1 team such as the 2024 Kansas City Chiefs might win close game after close game, constantly doing just enough to take home the W. This season’s Chiefs squad has 10 wins by one score, making them one of only four teams in NFL history with 10 or more one-score wins in a season (joining the 2022 Vikings, 2019 Seahawks and 1978 Oilers).

So are the 2024 Chiefs the “worst” 12-1 team in NFL history? I used my DVOA (Defense-adjusted Value Over Average) ratings, which are explained here, and point differential to answer that question and look at everything that has made Kansas City successful this season. Here’s a look at the five worst 12-1 teams of all time, starting with a different Patrick Mahomes-led Chiefs team.

Jump to where the 2024 Chiefs rank

5. 2020 Kansas City Chiefs

DVOA: 27.9% (led the NFL)
Point differential: +122

Here’s what I mean when I say that even the worst 12-1 teams are very good: The fifth-worst 12-1 team of all time was the best in the NFL that season. When the 2020 Chiefs were 12-1, they led the NFL in both DVOA and point differential. However, their schedule through 13 games was the fourth easiest based on the average DVOA of their opponents. Kansas City was 6-1 in one-possession games, as its only loss came to the Raiders in Week 5 by a 40-32 score.

What happened next: The Chiefs went on to win two more tight games by three points apiece over New Orleans and Atlanta, then sat their starters in Week 17 and lost to the Chargers. That gave them a 14-2 record to finish the regular season.

In the playoffs, Kansas City narrowly beat Cleveland after backup quarterback Chad Henne had to come in for an injured Mahomes. They had a convincing 38-24 victory over the Bills in the AFC Championship Game but lost starting left tackle Eric Fisher to a torn Achilles tendon. That compounded earlier injuries from the regular season, and with the offensive line in shambles, the Buccaneers crushed the Chiefs 31-9 to win Super Bowl LV.

4. 2008 Tennessee Titans

DVOA: 23.8% (fourth in the NFL)
Point differential: +148

The Titans had a mediocre offense led by veteran quarterback Kerry Collins but one of the league’s top defenses. They were only 4-0 in one-possession games. By point differential, they are not one of the five worst 12-1 teams, but the big difference between point differential and DVOA for Tennessee was schedule strength. The Titans’ schedule at 12-1 was the third easiest in the league, with big wins over the No. 32 Lions (who didn’t win a game), the No. 30 Chiefs, the No. 28 Bengals and the No. 26 Raiders. Tennessee’s only loss was in Week 12, 34-13 to an average Jets team.

What happened next: The Titans immediately lost a close game 13-12 to the Texans. After a more significant victory against the 11-3 Steelers, they sat starters in a Week 17 loss to Indianapolis and finished the regular season at 13-3.

The Titans were the No. 1 seed in the AFC, but they fell in the divisional round to wild-card Baltimore 13-10. Despite 391 net yards, the Titans could only get the ball in the end zone once. They turned the ball over three times while Baltimore never did, and Ravens kicker Matt Stover hit a game-winning 43-yard field goal with 57 seconds left.

3. 1990 San Francisco 49ers

DVOA: 21.4% (third in the NFL)
Point Differential: +98

This is the team I compare most to this season’s Chiefs squad. The 49ers were also trying to win a third straight title, and they had an underwhelming regular season where they won a lot of games in the final seconds. The 49ers beat the Saints on a field goal with 12 seconds left and then Cleveland on a field goal with nine seconds left. They beat Atlanta in Week 3 when Falcons quarterback Chris Miller mishandled the snap trying to spike the ball for a game-winning 47-yard field goal attempt. Does this all sound familiar?

Overall, the 1990 49ers were 7-0 in one-possession games in their first 13 games and had the 27th-ranked schedule in the league by DVOA.

What happened next: First, a win over the rival Rams. Then the 49ers lost 13-10 to New Orleans when running back Dexter Carter fumbled the ball away on the Saints’ 20-yard line with less than a minute to go. San Francisco’s backup quarterback Steve Young played the second half of the Week 17 game with Minnesota and led a game-winning touchdown drive that ended with 36 seconds left and a 20-17 victory which gave the 49ers a 14-2 record.

In the divisional round, San Francisco handled Washington easily 28-10. That set up an NFC Championship Game against the Giants, who were the best team by DVOA but were stuck playing backup quarterback Jeff Hostetler because of an injury to Phil Simms. Defensive end Leonard Marshall famously injured 49ers quarterback Joe Montana on a fourth-quarter sack, and when San Francisco tried to run out the clock on the next drive, running back Roger Craig fumbled twice, with the Giants recovering the second one.

Hostetler moved the ball down the field, and Matt Bahr hit a 42-yard field goal as time expired for a 15-13 win. The 49ers, dependent all season on last-second scores, had their season ended by one for the other team.

2. 1976 Oakland Raiders

Estimated DVOA: 20.4% (seventh in the NFL)
Point differential: +89

We’ll go back before the existence of DVOA ratings for the No. 2 team (DVOA goes back to 1979). The 1976 Raiders were the second-worst 12-1 team in terms of point differential, and a projected historical DVOA estimate ranked them seventh in the league for the entire regular season. One reason the Raiders have such a poor point differential is their only regular-season loss was huge. The Patriots stomped them 48-17 in Week 4.

Oakland was 6-0 in one-possession games that season. We don’t have access to the play-by-play details from all their games, but we know the Raiders beat the Steelers 31-28 in Week 1 despite being down 28-14 in the middle of the fourth quarter. They needed two fourth-quarter touchdowns to beat the Oilers 14-13 in Week 3, and they needed Bears kicker Bob Thomas to miss two field goals to beat Chicago 28-27 in Week 9.

What happened next: The Raiders finished the regular season 13-1 after perhaps their most convincing victory of the season, 24-0 over the San Diego Chargers. Then they started the playoffs by getting their revenge on the Patriots 24-21 in the Ray “Sugar Bear” Hamilton game. That close win also required two touchdowns in the fourth quarter.

But things got easier after that. First, the Raiders took out the defending Super Bowl champion Steelers 24-7 in the AFC Championship Game. Then the Raiders easily beat the Vikings 32-14 in Super Bowl XI.

1. 2024 Kansas City Chiefs

DVOA: 13.1% (eighth in the NFL)
Point differential: +56

The Chiefs have been the weakest of the 12-1 teams, despite their championship pedigree. There is a significant gap between them and the other 12-1 teams in DVOA and point differential. They are 10-0 in one-possession games and have won in some wild ways.

The Chiefs matched the 1990 49ers by winning a game in which the opposing team botched a snap in field goal range (against the Raiders in Week 13). They avoided overtime against Baltimore when Isaiah Likely‘s toe came down out of bounds on a game-tying touchdown. They blocked the game-winning field goal against Denver. A win over Cincinnati required a defensive pass interference penalty on fourth-and-16. And they beat the Buccaneers in overtime with a touchdown on their first possession.

One thing the Chiefs don’t have going in their favor is schedule strength. They aren’t overrated because of an easy schedule, as their past schedule ranks 14th by the average DVOA of opponents. But it is very hard to consistently win close games at this rate over the long term. Based on points scored and allowed, a team that outscored opponents 308-252 would normally be 8-5, not 11-1.

Why are the Chiefs statistically worse than in past seasons? Most of the blame has been put on the injuries on the offensive side of the ball, with running back Isiah Pacheco out for 11 weeks with a broken leg and receivers Rashee Rice (knee) and Hollywood Brown (shoulder) lost for the regular season. (Brown is expected back in January.) Still, the Chiefs rank only ninth in offensive DVOA; that’s not much different than ranking eighth in 2023.

Instead, the bigger problem has been the decline on defense in recent weeks. In Weeks 1-7, they ranked second in defensive DVOA behind only the Vikings. In Weeks 8-14, they have ranked 29th in defensive DVOA. Some of the explanation is the injury to cornerback Jaylen Watson (fibula/tibula), but this decline can’t just be tied to a single player. Turnovers are a problem, as the Chiefs have just one interception and two forced fumbles since Week 8.

There are 36 teams in NFL history that started a regular season either 12-1 or 13-0, including this year’s Chiefs and Lions. Out of those 36 teams, the Chiefs have the lowest point differential by more than 30 points. The Chiefs also have the lowest DVOA of any of these teams. (The 2015 Panthers were the lowest 13-0 team, by the way.) It takes a great team to start a season 12-1, but some team has to be the worst among those great squads, and it’s the 2024 Chiefs.

What happens next? The Chiefs have four remaining games in the regular season, three of which are on the road. ESPN’s Football Power Index (FPI) gives the Chiefs surprisingly similar odds on their final four games. They come out with a 52% chance to win in Cleveland this week, a 61% chance to beat Houston in their final home game, a 52% chance to beat the Steelers on Christmas and then a 60% chance to win in Denver in the final week — assuming they aren’t sitting starters with the AFC West already clinched. And speaking of playoff seed, now that they have a two-game lead on Buffalo and Pittsburgh, the Chiefs end up with the No. 1 seed in the AFC in 76% of FPI’s simulations.

Because they are likely to have that top seed, the Chiefs make the divisional round in 91% of ESPN’s simulations. They make it to the AFC Championship Game 53% of the time and win that game 26.6% of the time. FPI lists them with an 11.2% chance to win the Super Bowl, which ranks third behind Detroit and Buffalo. The Chiefs may be the worst 12-1 team ever, but that No. 1 seed — and home-field advantage — is useful to have.

Only six of the 21 teams that have started the season 12-1 since 1966 ended up winning the Super Bowl (1975 Steelers, 1976 Raiders, 1984 49ers, 1985 Bears, 1991 Washington and 2004 Patriots). Still, it’s not ridiculous to think that the Chiefs might turn it on in the postseason and win the Super Bowl based on Mahomes and coach Andy Reid’s recent history. Or they could watch clutch performances turn around and bite them in the backside, with close playoff losses like the 1990 49ers and the 2008 Titans.

We don’t know, and that’s why the games are played.