The 49ers are three-point favorites to beat the Packers tonight. In the NFL, home field advantage is worth three points, so if this game were to be played on a neutral field, odds-makers wouldn't know which team to favor.

A strong case can be made for both teams. The Packers have an outstanding passing attack and the 49ers have a top-flight defense. One former NFL offensive coordinator thinks the Packers must execute efficiently on offense to win, while the 49ers' defense must pummel Green Bay quarterback Aaron Rodgers if they are to win.

If you go by the numbers, Rodgers has a stellar 39-to-8 touchdown-to-interception ratio, and he has an equally impressive 68 percent completion percentage and his passer rating of 108 is best in the NFL.

The former coordinator also cited an intangible.

"I think he, subconsciously, still has that chip on his shoulder after being passed over by so many teams on draft day," the coordinator said.

But Rodgers isn't Superman. He can't beat the 49ers by himself, as we learned in Green Bay's 30-22 Week 1 loss to San Francisco at Lambeau Field.

"To defeat the 49ers, Aaron Rodgers needs the cooperation of his wide receivers, tight ends and running backs," the coordinator said. "In some of Rodgers' biggest games in previous years, those guys have had too many drops and ran too many inefficient routes."

Most important, Rodgers will need better protection than last time, especially from tight ends and running backs laying down blocks before running their routes. That's because the Packers' offensive tackles are weak links when stacked up against the 49er defensive ends, especially in nickel situations.

Because the Packers have a so-so offensive line, Rodgers will need to make quick decisions and quick throws.

"To assist in pass protection," the coordinator said, "Rodgers cannot afford to pass up open receivers in his progression in anticipation of the bigger throw that, in some cases, has not materialized or has resulted in a sack."

That means Rodgers needs to get the ball out of his hand quickly early in the game so his tackles don't suffer a total loss of confidence in their ability to pass protect.

The Packers coaching staff, in particular head coach Mike McCarthy, also needs to put Rodgers in a position to succeed with creative play calling, something he did not do last time.

"Mike McCarthy has called a few more play-actions where Rodgers rolls outside the normal framework of the pocket ... " the coordinator said. "This type of play should assist in taking out some of the steam in the Niners' pass rush so it cannot just rush to a spot and find Rodgers waiting.

"The real key is going to be McCarthy's play calling because he often calls deeper passes consecutively and needs to mix in the screens, the quick game, pocket movement passes, the intermediate patterns as well as his &‘shot' plays and deeper patterns."

In the opening game, Rodgers appeared agitated and never got into a rhythm. That was specifically related to McCarthy's play calling.

On the 49ers' side of the ball, victory will depend on the defense's ability to pressure Rodgers.

If the 49ers can successfully bring pressure up the middle, they may be able to flush Rodgers toward their dangerous edge rushers, Aldon Smith and Ahmad Brooks. If there's pressure up the middle, Rodgers may slide directly into a rusher on the edge and get sacked.

Pressuring Rodgers up the middle is the key. It will make things easier on the Niners' secondary, a unit that's at a disadvantage facing Green Bay's elite receiving corps. If the Packers must use maximum protection involving their tight ends and running backs, the Niners' secondary should do better in coverage.

"The biggest mismatch in the game is the Niners' slot pass defenders, Carlos Rogers and Perrish Cox, against Green Bay's receivers," the coordinator said.

Remember, the Rams feasted on the slot with more than 20 receptions by Danny Amendola and Chris Givens in two games against the Niners. McCarthy has seen the film and almost certainly will vary formations to get an assortment of receivers in the slot to see who does best against San Francisco's secondary.

"Vic Fangio needs to do something new and exotic with the defense," the coordinator said. "The typical man and zone coverages will not work on the Packers' slot receivers."

Fangio has two ways to show different looks, the coordinator said. Fangio can use a "man-under trail scheme," in which the slot cornerback actually lets the wide receiver beat him at the line of scrimmage and then follows the receiver wherever he goes.

Or Fangio can use a "short and long concept," where the defender jams the receiver at the line of scrimmage and then backs off and plays zone coverage while a deeper defender picks up the receiver man-to-man.

Notice the coordinator talks about offense in terms of the Packers, but defense in terms of the Niners.

To simplify the equation, understand this: If the Packers win, they'll do it with offense. If the 49ers win, they'll do it with defense.