The Seattle Seahawks will look avoid three consecutive losses to start the season when they host the Dallas Cowboys on Sunday at 4:25 p.m. ET. Seattle is a one-point favorite in the latest Cowboys vs. Seahawks odds, down from an open of -3. The over-under for total points scored has dipped to 40 after opening at 44.5. Seattle makes its home debut following a pair of one-score losses on the road to Denver and Chicago, while Dallas is looking to build on momentum from last week's primetime win over New York after losing its opener at Carolina. Before making any Cowboys vs. Seahawks picks, you need to hear what SportsLine senior analyst Josh Nagel has to say.

The handicapper has had a particularly sharp sense for the two clubs, posting a record of 13-3 in against the spread picks involving the Cowboys or Seahawks over the past two seasons. This includes an 11-2 mark on Seattle. Nagel improved on this record just last week when he advised SportsLine members to back favored Chicago against Seattle on Monday night. The Bears used a late pick-six to create separation and cover the spread in the 24-17 victory. 

Now, he has locked in on Sunday's showdown and analyzed all the key factors. He's sharing this selection over at SportsLine.

Nagel knows the new-look Seahawks have gone from a dominant club that was a heavy favorite to win the NFC West for the majority of this decade to an underdog to win eight games this season in the eyes of Vegas oddsmakers. Their over-under for total wins was 7.5, and they are now an even bigger underdog to finish at .500 after dropping two road games to start the season. Dallas is the first opponent on a brutal home slate that also includes visits from the Rams, Vikings, Chargers and Chiefs

Seahawks quarterback Russell Wilson has absorbed even more of the burden to produce on the offensive end and delivered with some explosive plays. He's done so without the services of top target Doug Baldwin, who was injured in the opener against Denver and is out for Sunday. Tyler Lockett has stepped up in Baldwin's absence with eight catches for 119 yards and two touchdowns.

There's also a revenge factor in this game. The Seahawks knocked the Cowboys out of playoff contention last season with a 21-12 win in Dallas in which they intercepted Dak Prescott twice and held the Cowboys' offense without a touchdown. It remains to be seen whether Seattle will cover as a slight favorite in the rematch.

So far, the Dallas (1-1) defense has been up to the task while splitting games against Carolina and New York. It has allowed just 29 total points, while ranking fourth in the NFL in total defense at 274 yards per game. 

But the offense has struggled to gain traction. Prescott has thrown for a modest 330 yards, one touchdown and no interceptions while completing 65 percent of his attempts. Star running back Ezekiel Elliott has 147 rushing yards and two scores to go along with 26 receiving yards. 

We can tell you Nagel is leaning over, but he has also identified the critical X-factor that makes one side of the spread a must-back. He's sharing what it is, and who to back, only at SportsLine.

Who wins Seahawks vs. Cowboys? And what critical factor causes one side of the spread to hit hard? Visit SportsLine now to see which side is a must-back, all from the senior analyst who's 13-3 on picks involving these teams.