Week 12 of the NFL ends with the Baltimore Ravens hosting the Houston Texans on Monday Night Football. The hometown Ravens are 7.5-point favorites, up a half-point from where the line opened.

The Over-Under, or total number of points Vegas thinks will be scored, is 39.5, up from an open of 38.

Before you bet on a primetime game like this, you'll want to hear what Vegas legend Micah Roberts has to say.

In Week 6, when the Texans hosted Cleveland as 9.5-point favorites, Roberts told readers to lay it without hesitation. The result: Texans 33, Browns 17. Strikingly, it was the third straight pick Roberts nailed for or against the Texans.

Part of his success: Roberts has worked in the Las Vegas sports book industry for 20 years, including a 13-year run as Station Casinos' book director. He can spot a bad line a mile away.

He's going for four in a row on "Monday Night Football," and you can only see what he's picking over at SportsLine.

Roberts knows that if it weren't for Joe Flacco's 11 interceptions, the Ravens would easily have the best turnover margin in the NFL. As things stood entering Week 12, Baltimore was +8, three behind Jacksonville's league-leading +11.

The Ravens' defense has been the reason they're in the running for a wild card. Baltimore is third in scoring defense at 17.1 points per game and has pitched three shutouts already (Bengals, Dolphins, Packers).

On Monday Night Football, SportsLine's advanced computer model says the Ravens will continue to bring the heat. It says Houston QB Tom Savage has a better chance of tossing an interception than a touchdown.

But just because the Ravens have been playing lights-out defense doesn't mean they win by more than 7.5.

The Texans just put up 31 points against Arizona. They ran for 134 yards and two touchdowns, while Savage notched the first multi-touchdown game of his career.

And despite Houston's recent issues at quarterback, wide receiver DeAndre Hopkins has scored nine touchdowns. The model projects Hopkins to top 70 yards on Monday Night Football and continue putting up chain-moving numbers.

The Ravens haven't been lighting up the scoreboard on offense, either. Flacco has thrown multiple touchdowns just twice and the Ravens' past two wins have come against teams quarterbacked by Brett Hundley and Jay Cutler.

Ravens RB Alex Collins has also struggled the last two weeks, rushing for a combined 92 yards. He found the end zone last week, but managed just 2.5 yards per carry with a long run of only nine yards.

And the Texans aren't getting blown out, despite losing defensive end J.J. Watt earlier this season. Four of their six losses have been one-score games.

It's no surprise Roberts is leaning toward the Under on "Monday Night Football," but what about against the spread, which he has made his name picking?

He knows there's a huge x-factor that ultimately determines the point-spread winner for Texans-Ravens. And he's sharing it over at SportsLine.

So which side should you back in Texans-Ravens on Monday night? Visit SportsLine now to see what big x-factor determines which side of Texans-Ravens you need to be all over, all from the expert who has nailed his past three Texans picks, and find out.