Seahawks vs. Cardinals NFL Week 18 props, odds: Arizona would be playoff spoiler, land over league-low preseason betting win total with upset victory

The Arizona Cardinals entered this season with the lowest over/under win total of any team on the NFL futures board at 4.5. They would exceed that number on Sunday in the regular-season finale by upsetting visiting Seattle, which has to win and get help elsewhere to have any shot at an NFC wild-card spot. The Seahawks are currently -3 on the SportsLine consensus.

Seattle (8-8) sits eighth in the NFC, losing a tiebreaker to fellow 8-8 team and No. 7 seed Green Bay (the teams didn't play this season) but winning one over 8-8 and No. 9 New Orleans (they didn't play either). The Seahawks would return to the playoffs with a victory and a Packers loss or tie. Green Bay is a 3-point home favorites against surging Chicago. Seattle also could get in with a tie, but would require even more outside help. DraftKings gives the Seahawks odds of +300 to make the playoffs and -400 to not. 

Bears-Packers and Seahawks-Cardinals both kick off at 4:25 ET – the NFL tries to schedule concurrent kickoffs by playoff relevancy in Week 18. It could therefore be tricky betting on Seattle against the spread if the team goes into halftime and sees the Packers up big against the Bears. Then again, if Green Bay is losing, it could also be a huge motivator for Pete Carroll's team.

Seattle, which had an opening O/U win total of nine, has lost five of seven following a 6-3 start and has failed to score more than 23 points in each of its past four games. The Seahawks also are 1-4 against the NFC West, although that victory came over Arizona, 20-10, in Week 7. Geno Smith threw for 219 yards and two scores and Kenneth Walker III had 105 yards on 26 carries. Joshua Dobbs and Clayton Tune took snaps under center for the Cards, but it will be all Kyler Murray on Sunday barring injury (Dobbs is lone gone).

First-year Arizona coach Jonathan Gannon already has anointed Murray as the unquestioned 2024 starter, so that apparently takes the Cards out of the QB derby at the top of the draft. They would currently pick fourth, but could get as high as second if both Washington and New England lose Sunday. The Commanders are largely expected to lose to the Cowboys.

"There is no doubt," Gannon said of Murray as his franchise QB. "I love [Murray]. Number 1 is our franchise quarterback. Being here with him for a year now, I'm more convicted than when I got here. Going through the process and our connection, developing a relationship with him."

The former No. 1 overall pick and Heisman winner has played solidly in seven games since his return from a torn ACL, completing 64.7% of his passes for 1,537 yards with nine TDs and five picks for an 86.8 passer rating. Murray also has rushed for 211 yards and three touchdowns on 39 carries. He is set at over/under 222.5 passing yards, 1.5 passing TDs and 31.5 rushing yards for Sunday. 

The Cardinalss are a weird team, as they are one of two clubs to beat both the Eagles and Cowboys this season, along with San Francisco, and own the NFL's highest strength of victory (.594). Arizona has lost three straight to Seattle, each by double digits. The Cardinals are 0-7 straight up and ATS in their past seven NFC West games.

One other interesting betting note: The Over is 7-0 in Arizona home games, the only unbeaten Over mark at home in the league. Cleveland has the lone unbeaten Over mark on the road (7-0) as it visits Cincinnati on Sunday. 

We'll see unusual NFL history Sunday. Seahawks defensive tackle Leonard Williams will be the first player to play at least 18 regular-season games in a season since 1930 when Tony Kostos and Cookie Tackwell both suited up for the Frankford Yellow Jackets and Minneapolis Red Jackets. Williams was traded from the Giants to Seattle on Halloween.

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