The New England Patriots and Jacksonville Jaguars meet Sunday in the AFC Championship Game. The defending Super Bowl champions are nine-point favorites, while the Over-Under, or total number of points Vegas thinks will be scored, is 46.5, down a half-point from an open of 47.

Before you bet on a playoff game like this, you'll want to hear what Mike Tierney has to say.

Tierney is a national sportswriter who has covered seven Super Bowls and has an extreme gift for picking Over-Unders. In the Wild Card round, Tierney boldly told SportsLine readers to go Under 48.5 in Falcons-Rams in a game many were convinced would go Over. The result: 39 total points and another easy cash.

That wasn't some lucky guess. Tierney has been crushing the books on these picks for two years now, going an astonishing 51-28 on NFL Over-Under picks since the beginning of last season. Those who have followed his picks have seen massive returns.

Now, Tierney has analyzed every matchup, every trend and every angle for the AFC title game and locked in his Over-Under pick. He's sharing it only over at SportsLine.

Tierney knows the Jaguars come into Sunday's game with the second-ranked scoring defense in the NFL, allowing 16.8 points per game.

Before the Steelers hung 42 on them, the Jaguars had allowed only 18 points total the previous two weeks to the Titans and Bills, both playoff teams.

Jacksonville is tops in passing yards allowed at just 169.9 per game, which could force the Patriots to lean on their rushing attack and slow the game down. On the other side of the ball, Jags RB Leonard Fournette had 109 rushing yards and three TDs last week. He's the centerpiece of Jacksonville's offense.

And 46.5 is the highest Over-Under for a Jaguars game all season.

But just because the Jaguars play stout defense doesn't mean the total goes Under, especially with Tom Brady on the field.

New England rarely reaches the Over on the road anymore, but at Gillette Stadium, the Pats have gotten there in eight of the past 11 games. Their postseason streak stands at four after New England toyed with Tennessee's defense last Sunday, scoring 35 points with ease.

And the Jaguars have been involved in several high-scoring affairs this season, including games that reached 82 total points (Steelers), 77 (49ers), 52 (Texans), and 54 (Seahawks). They sometimes get into shootouts.

Tierney has evaluated all of these circumstances and we can tell you he's leaning toward the Patriots covering the spread. He also knows there's a huge x-factor that ultimately determines whether Jaguars-Patriots goes Over or Under. And he's sharing it over at SportsLine.

So which side of the total should you back in Patriots-Jaguars? Visit SportsLine now to see what big x-factor sends Patriots-Jaguars Over or Under, all from the expert who's 51-28 on NFL totals picks since the start of last season.