The 49ers' 3 biggest concerns heading into Week 1 against the Seahawks

The last time these teams faced each other was Week 11 last season. That game was played in Santa Clara. The 49ers lost 20-17. Brock Purdy completed one touchdown pass, one interception and threw for just 159 yards (5.7 per attempt). Not good.

Keep in mind, the 49ers had Trent Williams, Christian McCaffrey, Ricky Pearsall and Jauan Jennings, who might not play in the season opener . They did not have George Kittle, who will make a big difference.

Still, the Seahawks have a terrific pass rush, excellent cornerbacks, and an outstanding defensive play caller in head coach Mike Macdonald. Meanwhile, the 49ers are decimated at wide receiver. They currently have Pearsall, Russell Gage, Skyy Moore and practice-squad players.

2. The run defense.

Darnold can make every throw, but he has terrible pocket presence, and he walks into sacks, so the Seahawks will try to limit the number of times he drops back. In addition, they have a new offensive coordinator, Klint Kubiak, whose running scheme is similar to the 49ers' scheme, considering he was on their staff two years ago, and his brother, Klay Kubiak, is the 49ers' offensive coordinator.

Plus, the Seahawks have two good running backs in Kenneth Walker and Zach Charbonnet, and a backup quarterback in Jalen Milroe who just might play a few snaps in the red zone to give the 49ers a different look.

That means the 49ers have to be prepared to stop a traditional running game with Darnold under center, as well as a college-style running game with Milroe in the shotgun. That's a lot to prepare for.

Meanwhile, the 49ers' first-round pick, defensive lineman Mykel Williams, missed all of preseason with a hyperextended knee. Their second-round pick, defensive tackle Alfred Collins, played but struggled. And their fourth-round pick, nose tackle C.J. West, missed the second two preseason games with a knee injury.

The 49ers drafted these three players to sure up their run defense. It's unclear if they're up to the task just yet.

3. Jake Moody.

Moody gave the 49ers every opportunity to cut him this offseason, but they refused. He lost a training camp kicking competition to Greg Joseph, but the 49ers cut Joseph anyway. Then in the preseason, Moody missed an extra point, almost missed another short field, missed a long field goal and booted a kickoff out of bounds.

After each blunder, Kyle Shanahan insisted that he remains confident in Moody. We'll see how much confidence Shanahan has in Moody if he misses a kick in this game.

Moody is under a ton of pressure because the 49ers drafted him in Round 3 two years ago. It's not enough for him to be an average kicker -- he has to be an excellent one. And through two seasons, he has been decidedly below average. And now he might have the yips.

If Moody costs the 49ers this game, they might cut him before they fly home.

No pressure, Jake.