The San Francisco 49ers enter Sunday’s NFC West showdown at Seattle aiming to crack the Seahawks’ defense, which has been among the NFL’s best this season. San Francisco’s offense, led by Brock Purdy, has started 4-0, one of only three teams with an undefeated record, while Seattle’s defense, coordinated by Mike Macdonald, has held opponents in check through four games, giving the Seahawks a 3-1 record. The winner will claim clear control of the division and stake a claim as the NFC’s top team.
Last season, the Seahawks’ defense stifled the 49ers in two critical meetings, including a 13-3 victory in Week 18 that secured Seattle the NFC’s No. 1 seed, followed by a 41-6 blowout in the Divisional Round. The defense’s success came largely through sub packages featuring nickel and dime personnel, led by safety Nick Emmanwori. Emmanwori, at 6-foot-3 and 220 pounds, combines size, speed, and versatility, allowing him to blitz, cover, and fill run gaps effectively. His presence lets Macdonald’s defense maintain pressure without sacrificing run defense.
In that Week 18 game, Seattle never deployed base defense during 42 snaps, instead relying on 31 nickel and 11 dime plays. The 49ers’ running game struggled as a result, gaining just 53 yards on 12 rushes with a negative expected points added (EPA) per rush. Tight end George Kittle, normally a dominant blocker in such situations, couldn’t open lanes. Purdy, who has emerged as one of the NFL’s best quarterbacks this season, finished 19-of-27 for 127 yards and an interception that day, hampered by the lack of a reliable ground game and Seattle’s defensive scheming.
Seattle’s defensive approach remained consistent in the playoffs, where sub packages featured on 50 of 60 snaps. The 49ers averaged under four yards per play and posted a negative EPA per play, reflecting the Seahawks’ grip on the contest. Emmanwori’s ability to play nickel on every down without weakening the run defense has been central to this success.
This year, the Seahawks’ defense ranks in the top five in most categories, despite early injuries to their secondary. They allow negative EPA on rushes while rarely stacking eight defenders in the box, which complicates San Francisco’s running attack. The 49ers’ ground game has been solid overall, ranking sixth in EPA per rush and success rate, but matching last season’s struggles against Seattle remains a challenge. Defensive lineman Leonard Williams missed practice on Thursday with an ankle injury, and fullback Kyle Juszczyk remains sidelined after a knee injury in Week 4, which could weaken San Francisco’s ability to run effectively.
Purdy has been the biggest difference for the 49ers this season. His combination of timing and improvisation has elevated the offense, which ranks as the NFL’s best so far. Purdy is tied for the league lead with 11 passing touchdowns. Alongside Mike Evans, who provides a reliable outside target, and Deebo Samuel with his gadget plays, the offense has more weapons than last year. Kittle’s return to form after an Achilles tear adds another dimension.
Kyle Shanahan’s reputation as a top offensive play-caller remains intact. His strategy is to dictate terms to defenses and exploit mismatches with misdirection and play-action. But Seattle’s use of Emmanwori in nickel packages has neutralized much of that, forcing the 49ers into predictable passing downs where Shanahan’s tactics lose effectiveness.
The 49ers will need Purdy to continue progressing and find a way to counter Seattle’s defensive looks if they want to win in Seattle. The Seahawks aim to extend their defensive dominance and secure first place in the division with a victory on Sunday.
According to Yahoo Sports.