The 5 biggest upsets of the 2023-24 NFL regular season

- Pre-game spread: 10 points
- Date: Dec. 4, 2023
- Final score: 34-31, OT

With Cincinnati Bengals franchise quarterback Joe Burrow out for the season, this game was pegged to be an easy win for the Jacksonville Jaguars, but it was anything but. Cincinnati backup Jake Browning came into his own in his second career start by completing 32 of 37 passes for 354 yards, including a 76-yard touchdown to Ja'Marr Chase.

With the game tied at 28 late in the fourth quarter, the Jaguars lost star quarterback Trevor Lawrence to an ankle injury. The momentum shifted, and the Bengals won with a field goal in overtime.

Jacksonville's loss marked the beginning of a downward slide—instead of moving into a three-way tie for the conference's top seed, it led the AFC South by just one game over the Houston Texans and Indianapolis Colts. Lawrence came back the following week but was ineffective in the next three games. The Jaguars managed only one more win during the regular season, finishing second in the division and missing the playoffs.

- Pre-game spread: 10.5 points
- Date: Dec. 25, 2023
- Final score: 20-14

The Las Vegas Raiders defense stunned the Kansas City Chiefs on Christmas Day with the help of a shockingly poor performance by the Kansas City offense. The team failed to pick up a first down on its first two possessions—an anomaly for quarterback Patrick Mahomes—but the worst was yet to come.

Kansas City had two costly turnovers in the second quarter—a fumble and an interception—that resulted in two Las Vegas touchdowns within 7 seconds. A missed field goal near the end of the first half didn't help the Chiefs, and even with a touchdown in the fourth quarter, they couldn't rally all the way back.

The loss kept Kansas City from clinching a playoff spot, but it eventually did win the AFC West.

- Pre-game spread: 11.5 points
- Date: Sept. 24, 2023
- Final score: 28-16

A month after he was traded to the Arizona Cardinals by the Cleveland Browns, quarterback Joshua Dobbs led the Cardinals to their first win of the season. It was his first victory as a starter in the NFL as well. The Dallas Cowboys were 2-0, having dominated both opponents—they made zero turnovers and racked up a plus-60 point differential, the team's best mark through two games since 1968. However, they were without star cornerback Trevon Diggs, who suffered a season-ending ACL injury during practice that week.

Like in its previous two games, Arizona was ahead at the break—Matt Prater made a half-ending 62-yard field goal, which turned out to be the longest in the NFL this season—but this time, it maintained the lead for all four quarters, holding Dallas to just one touchdown and three field goals. The Cowboys' lackluster performance included 13 penalties that set them back 107 yards.

The win was the one bright spot in Dobbs' time as a Cardinal. The team lost its next five games and then traded him to the Minnesota Vikings.

- Pre-game spread: 12 points
- Date: Dec. 31, 2023
- Final score: 35-31

Going into this matchup, the Philadelphia Eagles were atop the NFC East and seemed likely to coast to victory. The Cardinals were 3-12 and alone at the bottom of the NFC West.

Though they scored the opening points on a field goal, the Cardinals quickly fell behind—as expected—and by the half were down 21-6. Arizona tied it in the third quarter with two unanswered Kyler Murray touchdown passes, but with just 2 minutes and 33 seconds left in the game, the Eagles went ahead one more time on a 43-yard field goal by Jake Elliott.

Murray's passing got the Cardinals down the field quickly, however, and they went ahead on James Conner's 2-yard touchdown rush with just 32 seconds left. Eagles quarterback Jalen Hurts tried to get his team into the end zone, but his last-second Hail Mary pass was intercepted.

The Eagles' loss bled into the next week when they dropped their final game of the season to the New York Giants and had to settle for a wild-card slot in the playoffs.

- Pre-game spread: 13.5 points
- Date: Dec. 11, 2023
- Final score: 28-27

The Miami Dolphins were sitting pretty atop the AFC, hoping to cruise to their 10th victory of the year, when the 4-8 Tennessee Titans rolled into town. The game started as expected when Dolphins defensive tackle Zach Sieler got a pick-6 in the first quarter, but the Titans came back with 10 unanswered points to lead at halftime.

The teams traded field goals in the third quarter, but Miami stormed ahead in the fourth, scoring a field goal and two touchdowns to take a 27-13 with just 4:34 to play. Second-round draft pick Will Levis then stepped in, leading Tennessee to two touchdowns and completing a pass for a two-point conversion on the first. The Dolphins got the ball back with 1:49 remaining, but quarterback Tua Tagovailoa was sacked on fourth down, all but ending the game.

The loss shook up the Dolphins' playoff run—they went 2-2 to finish the season, settling for a wild-card slot. The glow of the win didn't last long for the Titans—they went 1-3 the rest of the way and then fired head coach Mike Vrabel.

Story editing by Mike Taylor. Copy editing by Robert Wickwire. Photo selection by Clarese Moller.