National Football League

NFL odds: Why big favorites rule Week 18 and more betting trends

Updated Jan. 5, 2022 7:31 p.m. ET

As NFL Week 18 approaches and teams contemplate their postseason fates, there are two trends attracting our attention this week: double-digit favorites' performance against the spread (ATS) and the frequency with which the under hits for the final regular-season game.

According to FOX Sports research, double-digit favorites have gone 22-14-1 ATS (59%) and 35-2 straight up during the final regular-season weekend since 2010. These big, 10-plus point favorites have also gone 7-2-1 ATS over the past two weeks.

With that in mind, let's take a look at the four games featuring big favorites — some of which have major playoff implications — and determine which bets offer some potential value.

Kansas City takes on Denver in a Saturday afternoon AFC battle that means little to the already-eliminated Broncos but has serious implications for the Chiefs.

Quarterback Patrick Mahomes, whose MVP odds sit at +2800 at FOX Bet, leads K.C. as 10.5-point favorites over 7-9 Denver with an over/under (O/U) of 44.5. Although they've clinched the AFC West division title, a win at Denver, coupled with a Tennessee loss, earns the Chiefs the AFC's No. 1 seed. You know Showtime is going to try to put on a spectacular performance to earn that first-round bye.

The next team that fits the trend is Tennessee. After running back Derrick Henry went down in Week 8 with a knee injury against the Colts, the Titans' fate was in limbo. Losing the man was leading the NFL with 937 rushing yards and 10 TDs over just eight games was a huge blow to its offense.

Surprisingly, the Titans bounced back and went 5-3 after losing Henry. Heading into Week 18, they're double-digit favorites against the Houston Texans. The O/U is set at 43, and the Titans are favored by 10.

Like the Chiefs, the Titans boast an 11-5 record, and they, too, have clinched their division. A win against the Texans — and a lot of help — could end with the Titans taking the No. 1 seed in the AFC. Will they try to run up the score?

Buffalo's matchup against the New York Jets is another double-digit favorite to watch, as the Bills enter this contest laying 16.5 points at FOX Bet with 41 as the O/U.

Quarterback Josh Allen has been fantastic this season, throwing for 4,168 yards and 34 TDs and currently has the sixth-best MVP futures (+2800) at FOX Bet. A win for 10-6 Buffalo, or a New England loss, will clinch the AFC East. Expect Allen and the Bills to put the rest of the division on notice with this weekend’s performance.

Finally, bettors should keep their eyes on the matchup between Indianapolis and Jacksonville. In terms of playoffs, the 2-14 Jaguars have known for weeks that they didn't have a realistic shot at the postseason. The Colts, though, have a lot on the line in Week 18.

Indy is favored by 15.5 points over the Jags and the O/U is 44. As for the Colts' playoff chances, they are in with a win or with help from the Chargers. Jacksonville is coming off of a 40-point loss to New England. Will we see more of the same this Sunday?

FOX Sports research also found that betting the under in certain weather conditions is a profitable bet during the last week of the season. Since 2003, the under has hit in 13 of 16 games (81%) in which the average wind speed over the course of the game is over 25 miles per hour. This means you should check the weather reports this week! It's also worth noting that since 2010, the under has hit in 20 of 37 (54%) final games of the regular season.

So looking at the trends, we know that betting the under has been profitable during the last week of the NFL season. Logically, it makes sense, as weather, motivation and the fact that playoff teams will want to avoid jeopardizing players' health heading into the postseason all come into play.

With these betting trends leading the way into Week 18, which of these matchups are you wagering on? Head over to FOX Bet to get in on the action now!

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