Upset alert in NFL Week 9? Why these favorites could fall, including Dak Prescott and the Cowboys

Bettors will need to have their heads on a swivel in Week 9. In correlation with Halloween, the upcoming slate has a chance to be more trick than treat. The NFL is coming off a couple of weeks where favorites have dominated. That includes Week 8, where favorites went 11-2 ATS. That 84.6% cover rate was the best since Week 16 in 1985. (Yes, you read that right). When you pair that with the Week 9 slate of games opening with nine home underdogs, there's the possibility for carnage as water finds its level.

That puts an ever greater emphasis on trying to find the mismatches this week and locate possible upsets, so that we ride with the underdogs instead of feeling their wrath. Below, we've identified five games where we could see upsets in Week 9.

NFL odds courtesy of FanDuel Sportsbook. Bet NFL at FanDuel and get $300 in bonus bets with a winning $5 wager.

Kansas City Chiefs (-1.5) at Buffalo Bills

• When: 4:25 p.m. ET | Where: Highmark Stadium (Orchard Park)
• TV: CBS | Stream: Paramount+
• Bills ML odds: +108

We've been looking forward to this heavyweight showdown ever since the 2025 regular season schedule was released. On the one hand, it was surprising to see the Bills as a home underdog with Highmark Stadium being one of the toughest places to play in the entire NFL. On the other hand, the Chiefs do seem to have flipped a switch in recent weeks, with Patrick Mahomes looking more like his old self just in time to square off against Josh Allen.

This rivalry has been one of the best in recent NFL history, but it is one-sided depending on when these games are played. In their all-time head-to-head, Mahomes bests Allen with a 5-4 record. However, four of those victories have come in the playoffs. In the regular season, Allen is the dominant one with a 4-1 record against Mahomes. Given that this game is being played in November and not January, Allen could have a leg up, making a home upset live no matter how well K.C. is playing. 

Arizona Cardinals at Dallas Cowboys (-3)

• When: Monday, 8:15 p.m. ET | Where: AT&T Stadium (Arlington)
• TV: ABC | Stream: (Fubo, try for free)
• Cardinals ML odds: +130

Kyler Murray is slated to return in Week 9 after being sidelined for the Cardinals' previous two games due to a foot injury. That's great news for Arizona as Murray is unbeatable when he's in Dallas. Literally. The Cardinals quarterback and Texas native is 9-0 in his football life at AT&T Stadium, ranging from high school, college, and the NFL.

While we note that history partially in jest, Murray and the Cardinals have an outstanding matchup against a poor Dallas defense. They are giving up 6.2 yards per play this season and are allowing opposing quarterbacks to register a combined 112.0 passer rating against them. Both of those figures are at the very bottom of the league.

While the Cowboys defense should give little resistance to the Cardinals offense, Arizona has a defense that could give Dallas some fits. They are holding quarterbacks to an 85.8 passer rating against (eighth in the NFL) and sturdy on third down, ranking sixth in the league with a 35.6% conversion rate. There's a clear path for Arizona to come out with an outright win in Week 9. 

Jacksonville Jaguars (-3) at Las Vegas Raiders

• When: 4:05 p.m. ET | Where: Allegiant Stadium (Las Vegas)
• TV: Fox | Stream: (Fubo, try for free)
• Raiders ML odds: +146

Both of these teams are coming off the bye in Week 8, so they'll have an equal rest advantage. While The Jags (4-3) are heads and shoulders above the Raiders (2-5) in the win-loss column, they are not a set-and-forget favorite. Jacksonville is coming off back-to-back losses where the offense has gone silent, averaging 9.5 points per game.

Through seven games, Trevor Lawrence has registered an 80.6 passer rating, which would be the lowest of his career since his rookie season if he holds. Part of the problem has been protection, as he's been sacked 20 times already. That's a long way in saying that the Jaguars offense isn't the most trustworthy unit at the moment, especially in a game where Maxx Crosby could take over.

While Geno Smith is hardly trustworthy, the Raiders are expected to get back two key weapons in the passing game in wideout Jakobi Meyers and tight end Brock Bowers. That should give Las Vegas a boost and keep them within range of the spread/possible upset. 

Chicago Bears (-2.5) at Cincinnati Bengals

• When: 1 p.m. ET | Where: Paycor Stadium (Cincinnati)
• TV: CBS | Stream: Paramount+
• Bengals ML odds: +120

The Bengals defense is bad, and just allowed Justin Fields and the previously winless New York Jets to drop 39 points against them in Week 8. With that in mind, it's not surprising to see them as home dogs. However, it's flown a bit under the radar how poorly Caleb Williams has been playing in recent weeks. He's gone back-to-back games with zero passing touchdowns and one interception.

Even worse, he has a league-low 16% off-target rate on his throws this season despite having the longest average time to throw (3.21 seconds). If that persists in Week 9, Cincinnati's defense may get some gifts that could help push the club to a win. 

On the other side, Joe Flacco has been an upgrade over Jake Browning at quarterback and has effectively been able to get the football to his playmakers like Ja'Marr Chase and Tee Higgins. Flacco has eight total touchdowns and zero turnovers in his three starts with Cincinnati. With that in mind, just a slight improvement on defense (maybe aided by Williams) should help the Bengals if Flacco keeps his play up. 

Denver Broncos vs. Houston Texans (-1.5)

• When: 1 p.m. ET | Where: NRG Stadium (Houston)
• TV: Fox | Stream: (Fubo, try for free)
• Broncos ML odds: +100

C.J. Stroud finally looked like his old self in Week 8, logging his first 300-yard passing game of the season. Arguably, the biggest reason for his return to form last week was that he took zero sacks in the win over San Francisco. Will that continue, or what that a one-off performance from the offensive line? Something tells me that Stroud won't go unscathed in Week 9 against a Denver pass rush that is the NFL's best.

The Broncos are tied for fifth in the league in pressure rate and lead the NFL with 36 sacks on the year, which is 10 more than any other team. If Denver continues that stellar pace, Stroud could be thrown off his game and put the Texans offense back into neutral.

Even if the Broncos can't get home, their prowess in the red zone is a major mismatch. Denver is holding opponents to touchdowns on just 40% of their trips to the red zone, which is tied for the NFL's best. Meanwhile, the Houston offense is scoring touchdowns on just 42.1% of trips, which is second-worst in the league. If all the Texans can muster are field goals, they'll have a hard time defending their home turf.