49ers vs. Packers preview: The Niners are three-point favorites in their home opener

The San Francisco 49ers have their home opener Sunday night against the Green Bay Packers, where they'll wear the famous '94 red throwbacks.

Jimmy Garoppolo was asked if he and his teammates were excited:

“Hell yeah. Yeah, it’s been awhile. The Packers were the last team actually with a crowd here. So, it’s a kind of coming full circle now, but it will be exciting getting the faithful back in the stands. I can’t wait to get all them screaming and everything like that. It’s going to be a fun atmosphere.”

There aren't many better environments than a night game at Levi's Stadium.

The 49ers are three-point favorites over the Packers, with the total on the game set at 50.5. Vegas is expecting the Niners to win 27-24.

During this week's episode of The Shanaplan with Akash, I told him I felt more confident about this week's game against the Packers than last week's against the Eagles. Green Bay isn't nearly as stout as Philly in the trenches on both sides of the ball.

The real reason is their defense. The Packers are 26th defensively in EPA per play, 30th in defensive success rate, 28th in dropback EPA per play, 31st in dropback success rate, and 28th in defensive DVOA.

Green Bay has played New Orleans and Detroit — two teams without a No. 1 receiver. When you watch the Packers, you'd think Mike Pettine was still in charge. The secondary looks lost and often out of position.

I mention the Packers' passing numbers because this should be where the 49ers' passing offense goes from efficient to explosive. Despite Jimmy Garoppolo only throwing the ball over 20 yards twice in the air this season, San Francisco has generated the 14th-most explosive passing plays.

When I watch the 49ers through the first two games, it seems like Kyle Shanahan has been playing it close to the vest. Against the Eagles, they put their head down, ran into a wall, threw short passes, and got the you know what out of dodge.

That changes this week.

Josh Sweat, Brandon Graham, Derek Barnett, and Fletcher Cox isn't on that other sideline this week. Green Bay has one sack on defense this season. They're without Za'Darius Smith, their best pass rusher.

The Packers will trot out a bunch of "big" bodies who can't threaten Mike McGlinchey with speed around the edge or the interior offensive line with quickness off the snap. This bodes well for Garoppolo dropping bak and the offense taking more shots down the field.

The speed on the 49ers' offense should be too much for the Packers to handle. However, success through the air should open up the running game. Garoppolo should continue to play "point guard," and if he can hit the deep shot Sunday night, I have a tough time seeing the Packers slowing down the Niners at home.

DeMeco Ryans first real challenge

The 49ers are going to score points. Can the Packers keep up? How will Ryans do against a superstar QB? Davante Adams had eight catches for 121 yards, and while Deommodore Lenoir has been sound, you have to imagine there will be a bullseye on the rookies' back in this one.

You can put an asterisk next to San Francisco's defensive metrics as they're skewed thanks to the drives by the Lions at the end of the game, a 91-yard pass against the Eagles as well as Philadelphia's drive towards the end of the game where Jalen Hurts strolled down the field to score.

The Packers' offense hasn't been as high-flying through two games as you'd expect. They don't have a carry for more than 15 yards and only have two passing plays over 20 yards. Those numbers are good for dead last and second to last.

We knew there would be more variance from Ryans than Robert Saleh when it comes to giving up the big play. San Francisco has allowed the sixth-most explosive passing plays and third-most explosive running plays.

The 49ers are 10th in the NFL in dropback success rate. On a play-by-play basis, the secondary has performed well. It's those big plays, albeit during parts of the game that didn't feel like they mattered, that's hurt the 49ers' defense.

The Packers are 20th in passing DVOA and 24th in rushing DVOA. They're already down David Bakhtiari. His replacement, Elgton Jenkins, has an ankle injury. The Packers are giving Jenkins all week to recover to determine whether Jenkins can play. If he does suit up, the odds that Jenkins is 100% is slim.

If your weakness is your offensive line, good luck against the 49ers. That could force Green Bay to get the ball out of Rodgers's hands quickly. Sustaining double-digit play drives against the Niners doesn't happen. That's not how you score on this team.

Because of that and the recent history between these two teams when they are healthy, I like the 49ers to cover.

Five keys to a 49er win:

• 5+ explosive plays on offense
• Two double-digit play drives on offense
• Zero turnovers
• 3+ sacks on defense
• Hold Adams under 80 yards