The Seahawks host the 49ers on Sunday at Lumen Field in a big NFC West clash between a pair of teams that, once again, look to be among the best in the league. The 49ers are off to a 4-0 start, making them one of three unbeaten teams left in the league heading into Week 5, while Seahawks are a game back in the standings at 3-1.

It's the first meeting between the teams since the Seahawks beat the 49ers 41-6 in the Divisional Round of the playoffs, their second win over San Francisco in a two-week span, having also won in Santa Clara in Week 18 to clinch the NFC West title and the NFC's top seed. And while the Seahawks will be looking to continue that success, which included two full games without giving up a touchdown, the 49ers, who already beat the Rams in Week 1, are trying to put themselves in the early driver's seat in the NFL's toughest division.

With that in mind, here are five things to watch when the Seahawks and 49ers face off on Sunday afternoon.

1. Can the Seahawks defense pick up where it left off last season against the 49ers?

The Seahawks' march to a Super Bowl title included a pair of key victories over the 49ers. The first, a Week 18 game in Santa Clara, saw the Seahawks win 13-3 to earn the NFC West title and the conference's top seed. Two weeks later in the Divisional Round, the Seahawks won 41-6 at Lumen Field, kicking off a postseason run that finished with a Super Bowl LX win at Levi's Stadium.

In those games, the Seahawks held the high-octane 49ers offense to only three field goals, 409 total yards and 24 first downs while forcing four turnovers over the course of eight quarters.

The Seahawks, of course, know they can't just assume this game will go like those two did, despite having a lot of continuity from last year's defense. Every team changes over the course of an NFL offseason, and ideally, gets better, and the 49ers are no exception.

Quarterback Brock Purdy, the NFC Offensive Player of the Month for September, has thrown a league-leading 11 touchdowns with just one interception, and he leads the NFL in passer rating (126.2). Perhaps most importantly, he has yet to take a sack through four games.

The Seahawks defense, with the exception of a few lapses, many of them self-inflicted, has again been great, but it will take a very strong performance to slow down one of the NFL's hottest offenses.

"Good team football," Seahawks coach Mike Macdonald said. "They're running the ball, they're staying ahead of schedule, limited third downs. When they throw it, they're playing on time. There haven't been many occasions where there's people unaccounted for for the quarterback, and when there has been, he's gotten rid of the ball. We spoke about how he's been able to extend plays and take care of the football and still have that element of creativity and playmaking that keeps the ball moving forward. They've been doing a great job."

2. Will Jaxon Smith-Njigba and the rest of Seattle's playmakers find ways to make explosive plays against a stingy 49ers defense?

The 49ers have pretty consistently been a good defensive team throughout Kyle Shanahan's tenure as head coach, despite some frequent changes at defensive coordinator. And with Robert Saleh leaving this offseason to become the head coach of the Titans, the 49ers are again playing defense at a high level under a new coordinator, this time former Falcons head coach Raheem Morris.

The 49ers are doing a lot of things well on that side of the ball, and as a result have allowed the third fewest points in the league. A big reason for that defensive success has been San Francisco's ability to limit big plays. Through four games, the 49ers have allowed only six pass completions of 20 or more yards, tied for the second fewest in the league behind the Seahawks and Rams, who have allowed five such completions. They're also one of six teams to not allow a rush of 20-plus yards this season.

Per Next Gen Stats, the 49ers have allowed a league-low 33.3 completion percentage on downfield passes (10-plus air yards) this season, just ahead of the Seahawks (34.5 percent), making those two teams the best, by far, at eliminating downfield completions -- no other team in the league has held opponents below 40 percent on downfield throws.

The Seahawks will counter, of course, with a passing game that features Sam Darnold, a great downfield thrower, connecting with the NFL's best receiver in Jaxon Smith-Njigba, a player who this season has already scored touchdowns on completions of 82 and 45 yards, and who has receptions of more than 25 yards in each of his first four games.

The Seahawks will still try to play their game, and part of that is making plays downfield, but they also know they can't force the issue against a defense as good as San Francisco's.

"They do a good job," Darnold said. "Getting into the nitty-gritty, their backers, their back end and their rush all being tied together, they do a good job with that. Keeping everything in front of them. They do a good job of tackling as well, which helps limit those explosives.

"You always want to stay on schedule as a quarterback. First and second down, staying on schedule, keeping the ball moving forward. Explosives will come. I don't think you're ever hunting explosives, they come naturally within the game plan. That's going to be our mindset going out there."

3. What kind of difference do offseason receiver acquisitions Mike Evans and Deebo Samuel make for San Francisco's offense.

As mentioned earlier, the Seahawks know they can't count on last year's defensive success carrying over just because of how things went in January, and part of the reason why is that the 49ers have added some playmakers to their offense.

For as good as San Francisco was on offense for most of last season, they at times lacked playmakers at receiver in part due to injury, and they addressed that spot this offseason, signing veteran Pro Bowl receiver Mike Evans and bringing back longtime versatile receiver Deebo Samuel. And four games into the season, both of those players have been difference makers for San Francisco's offense, giving the Seahawks two more things to worry about on Sunday.

"Mike Evans is a hell of a player," defensive coordinator Aden Durde said. "His ability to catch the ball and carry the ball downfield shows up, still shows up. The things that get missed with that guy is his toughness in between the paint and the way he plays the game. He brings a lot to them. Deebo coming back, putting him in the backfield, moving him around, he presents problems. Throughout these weeks, it's about how we deal with things and about how we play. That's the thing to focus on."

4. Does Rashid Shaheed get more touches in the run game?

In high school, and early in his college career, Rashid Shaheed was a dynamic running back right up until the point he recognized that he was never really going to have the size to play that position at the next level.

"Once I figured out that I wasn't going to be a big person, I made that decision that I didn't want to get hit by linebackers," Shaheed said.

The move to receiver paid off for Shaheed, who has made a very good NFL career for himself as a big-play receiver and one of the league's top returners, but as he showed in Sunday's win over the Chargers, Shaheed can still make things happen out of the backfield. Debuting a look the team has been working on since training camp, Shaheed lined up in the backfield on a few occasions on Sunday, carrying twice for 33 yards, including a 28-yard touchdown.

With rookie running back Jadarian Price, himself a speedy, big-play threat, currently on injured reserve, there's a good chance Shaheed will continue to see touches out of the backfield, both because it produced results last week, and also because it gives opponents one more thing to worry about when game-planning for Seattle's offense.

"Anytime you can add a different element to the backfield with different players, it just gives you a little bit more diversity and makes the defense prepare for different types of plays," offensive coordinator Brian Fleury said. "It's something we actually have been doing since, I think, at least training camp, if not even the spring, in anticipation that a situation like this might come up. So, he was ready for it."

5. Will this week's defensive player-led meeting to address the penalty issues pay dividends?

The Seahawks won in Week 4, beating the Chargers 30-23, but that final score was a lot closer than it needed to be, thanks in large part because of penalties. Both Chargers touchdowns came on drives that were extended by two personal foul penalties, including two roughing the passer calls on third and long that negated stops that would have otherwise forced punts. And in the first half, there was an after-the-whistle personal foul on Nick Emmanwori, who otherwise had a great game, that put the Chargers in field goal range, more or less gifting them three points.

Because of those penalty issues, defensive veterans like Leonard Williams, Ernest Jones IV, Jarran Reed and Julian Love called a "real, honest" meeting to face the problem head on.

"We got together as a defense on Monday, players only, and we just had a real, honest meeting with each other about what we expect and what we want to go through," Reed said. "We hit it head on, because that was way too many penalties for us as a team, especially the personal (foul) penalties. Some of the stuff is just the cost of doing business, but the ones that can be avoided, we need to avoid those penalties.

"We've got to be smart. The guys play hard and we like to be a physical group. Sometimes just the way the rules are in the league, there's a lot of stuff that we can't do. We're just not there, and we can't just try to do too much or overdo, but the guys are playing hard, it's a testament to them. Once you get to the situation, if you think it's going to be a certain type of flag situation, we've got to be smart."

The Seahawks defense has given up very little this year without opponents benefiting from penalties or turnovers, but in games where those issues have come up, they have been the only real avenue for opponents to put up a significant number of points. Facing the best offense they have seen this season, and one of the best in the league, period, the Seahawks defense will need for those messages in this week's players-only meeting to result in a cleaner game.