In a potential playoff preview, the 10-1 Saints visit the 6-5 Cowboys on Thursday Night Football in the first game of the Week 13 NFL schedule. It's an 8:20 p.m. ET kickoff from AT&T Stadium. Behind 39-year-old quarterback Drew Brees, New Orleans continues to set offensive records as it seeks an 11th straight win, while Dallas controls its own destiny in the NFC East after beating the Redskins on Thanksgiving Day for its third victory in a row. Both teams are above .500 against the spread this season and have covered their last three games. Sportsbooks list New Orleans as a touchdown favorite, with the over-under for total points set at 51.5 in the latest Cowboys vs. Saints odds. Before you make any Cowboys vs. Saints picks, see what No. 1 NFL expert Larry Hartstein has to say.

SportsLine's senior analyst and resident Saints expert has nailed six straight spread picks for or against New Orleans, including another easy winner on Thanksgiving. That made him an insane 17-5 in his last 22 picks involving the Saints. Moreover, he's the No. 1 NFL expert on SportsLine, sporting a ridiculous 44-19 record this season. Anyone following his picks is up over $2,200.

Now, Hartstein has pounced on what he calls a mistake in the spread for Saints vs. Cowboys (stream live on fuboTV). He's only sharing his pick at SportsLine. 

Hartstein knows the Saints have buckled down defensively lately, complementing their top-ranked NFL offense. New Orleans held Tevin Coleman and the Falcons to 26 net rushing yards in a 31-17 home win on Thanksgiving and also registered season highs in sacks (six) and forced turnovers (four).

New Orleans' last three opponents (Bengals, Eagles, Falcons) have failed to crack 20 points. Meanwhile, the Saints' 31 points scored last week represented their lowest total since Week 8.

And at age 39, quarterback Drew Brees appears poised to grab his first MVP award: he's hitting 76.4 percent of his throws with 29 touchdowns and two interceptions. He has an incredible 15 passing touchdowns the last four games.

But just because the Saints have covered nine straight doesn't mean they'll do it again against a streaking Cowboys team. 

Dallas running back Ezekiel Elliott has rushed for at over 120 yards the past three weeks, averaging a stunning 5.8 yards per carry. He's up to eight total touchdowns this season and is benefiting from improved offensive line play and a new downfield threat in wide receiver Amari Cooper, who was acquired from Oakland for a first-round draft pick. 

If Zeke has similar success on Thursday Night Football, Dallas will control the clock and keep its defense fresh. The unit has been much better than expected: the Cowboys allow 19.4 points per game, fourth-fewest in the league, and just 3.7 yards per carry. Dallas has held the Eagles, Falcons, and Redskins to 23 points or fewer during its three-game win streak and is second in the NFL in sacks with 38.

We can tell you Hartstein is leaning Over, but his much stronger play is against the spread. He knows a critical x-factor makes one side of the spread a must-back. He's sharing what it is, and who to back, only at SportsLine.

So who wins Saints vs. Cowboys? And what critical x-factor causes one side of the spread to hit hard? Visit SportsLine now to see which side you need to be all over, all from the unparalleled expert who's an outstanding 17-5 on spread picks involving the Saints, and find out.