The Minnesota Vikings visit the Detroit Lions in the first game of the NFL's Thanksgiving Day triple-header. The game opened as a pick' em, which means neither team was favored, but the Vikings are now three-point favorites.

The Over-Under, or total number of points Vegas thinks will be scored, is 44.5, down a half-point from where it opened.

Before you make any bets on a game like this with so much Vegas odds movement, you'll want to hear what SportsLine Senior Analyst Larry Hartstein has to say.

He has his finger on the pulse of Mike Zimmer's Vikings. In Week 11, he told readers not to hesitate and lay 2.5 points with Minnesota vs. the Rams, noting L.A. had built up its NFL-best offensive numbers against lackluster defenses. The result? Vikings 24, Rams 7 -- another easy cash.

Strikingly, it improved his record to 7-1 picking for or against the Vikings. And he's also on an 8-2 run in against the spread picks. Anyone who has followed his picks is up big-time.

Hartstein has evaluated Lions vs. Vikings on Thanksgiving Day from every conceivable angle and locked in his pick. And he's sharing it over at SportsLine.

Hartstein knows this is a game with streaks on each side. The Lions have beaten the Vikings three straight times and Detroit has won four straight on Thanksgiving. The Lions also have covered the spread in five straight Thanksgiving games.

But just because the trends favor Detroit doesn't mean the Lions, who are coming off a down-to-the-wire finish at Chicago, stay within a field goal of the red-hot Vikings.

The Lions come into Thanksgiving Day football on a three-game win streak, but those victories came against the Aaron Rodgers-less Packers, Browns, and Bears.

Meanwhile, the Case Keenum-quarterbacked Vikings are winners of six straight, including impressive victories over the Rams (7-3) and Ravens (5-5).

Vikings WR Stefon Diggs has eight catches and a score since returning from a groin injury, while Adam Thielen has come into his own and scored in three straight contests.

Thielen, in his fourth season, is second only to Antonio Brown in receiving yards with 916. He has double-digit targets in four of his last five games and has topped 100 yards in two straight outings.

It's no surprise Hartstein is leaning Over on the opening Thanksgiving Day NFL game, but what about against the spread, which he's made his name picking?

So which side should you back in Lions-Vikings on Thursday? Visit SportsLine now to see what critical x-factor you're not even thinking about determines which side of Lions-Vikings you need to be all over, all from the expert who is 7-1 on Vikings picks, and find out.