The Seattle Seahawks visit the Green Bay Packers on Sunday afternoon in a showdown of NFC heavyweights. Green Bay has won the last two meetings, both at home, by a combined 55-27 score.

The Packers have held steady as three-point favorites, while the Over-Under, or total number of points Vegas thinks will be scored, stands at 50 after an open of 49.5.

Before you bet on a high-profile game like this, you'll want to hear what veteran handicapper Josh Nagel has to say. He's won numerous handicapping contests and been in the industry for nearly 20 years.

A West Coast insider, he's a whiz at picking Seahawks games, regardless of who they're playing. He went 4-1 picking for and against them last year and had his finger on the pulse of Pete Carroll's team.

When the Seahawks traveled to Green Bay last December, Nagel was all over the Packers as three-point underdogs. The result: Russell Wilson tossed a career-high five INTs and the Pack romped 38-10. It was his fourth win in five games involving the Seahawks.

Nagel knows Sunday's game comes down to the Seahawks' defense (No. 3 in scoring last year at 18.3 ppg allowed) against a Packers team that added weapons for quarterback Aaron Rodgers like tight end Martellus Bennett.

If the Seahawks can pressure Rodgers and force turnovers, they'll win on the road. But will that happen? Nagel knows the Seahawks were 2-5 against the spread on the road last season, while the Packers are 4-0 against the spread in their last four home games.

The Packers used their first four draft picks to bolster a defense that was No. 22 overall last year and showed its glaring shortcomings in a playoff loss to the Falcons. In that game, Matt Ryan had a field day, throwing for 338 yards and three TDs. But will they be able to slow down Wilson, who looked red-hot in the preseason?

Nagel thinks Seahawks vs. Packers will probably be a low-scoring game that stays Under, but there's one team he thinks is a very strong play to cover. He's sharing which one it is over at SportsLine.

So which side of Seahawks-Packers should you take? Visit SportsLine now to see what huge x-factor determines Seahawks-Packers, and what team is a very strong play to cover, all from the handicapper who's nailed four of his last five Seahawks picks.